User:BudjarnLambeth/Basal subgroup: Difference between revisions

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m BudjarnLambeth moved page Basal subgroup to User:BudjarnLambeth/Basal subgroup
 
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Line 31: Line 31:
=== ed3/2, ed5/2, ed7/2, ed11/2... ===
=== ed3/2, ed5/2, ed7/2, ed11/2... ===
A.k.a. "[[half-prime subgroup]]s".
A.k.a. "[[half-prime subgroup]]s".


To find BSGn/2:
To find BSGn/2:
Line 52: Line 51:
=== ed5/3, ed7/3, ed11/3, ed17/3... ===
=== ed5/3, ed7/3, ed11/3, ed17/3... ===
A.k.a. "[[half-prime subgroup|third-prime subgroups]]".
A.k.a. "[[half-prime subgroup|third-prime subgroups]]".


To find BSGn/3:
To find BSGn/3:
Line 72: Line 70:
=== ed5/4, ed7/4, ed11/4, ed17/4... ===
=== ed5/4, ed7/4, ed11/4, ed17/4... ===
A.k.a. "[[half-prime subgroup|quarter-prime subgroups]]".
A.k.a. "[[half-prime subgroup|quarter-prime subgroups]]".


To find BSGn/4:
To find BSGn/4:
Line 92: Line 89:
=== ed7/5, ed11/5, ed17/5, ed19/5... ===
=== ed7/5, ed11/5, ed17/5, ed19/5... ===
A.k.a. "[[half-prime subgroup|fifth-prime subgroups]]".
A.k.a. "[[half-prime subgroup|fifth-prime subgroups]]".


To find BSGn/5:
To find BSGn/5:
Line 111: Line 107:
=== ed7/6, ed11/6, ed17/6, ed19/6... ===
=== ed7/6, ed11/6, ed17/6, ed19/6... ===
A.k.a. "[[half-prime subgroup|sixth-prime subgroups]]".
A.k.a. "[[half-prime subgroup|sixth-prime subgroups]]".


To find BSGn/6:
To find BSGn/6:
Line 130: Line 125:
=== ed11/7, ed17/7, ed19/7, ed23/7... ===
=== ed11/7, ed17/7, ed19/7, ed23/7... ===
A.k.a. "[[half-prime subgroup|seventh-prime subgroups]]".
A.k.a. "[[half-prime subgroup|seventh-prime subgroups]]".


To find BSGn/7:
To find BSGn/7:
Line 148: Line 142:
=== ed11/8, ed17/8, ed19/8, ed23/8... ===
=== ed11/8, ed17/8, ed19/8, ed23/8... ===
A.k.a. "[[half-prime subgroup|eighth-prime subgroups]]".
A.k.a. "[[half-prime subgroup|eighth-prime subgroups]]".


To find BSGn/8:
To find BSGn/8:
Line 166: Line 159:
=== ed11/9, ed17/9, ed19/9, ed23/9... ===
=== ed11/9, ed17/9, ed19/9, ed23/9... ===
A.k.a. "[[half-prime subgroup|ninth-prime subgroups]]".
A.k.a. "[[half-prime subgroup|ninth-prime subgroups]]".


To find BSGn/9:
To find BSGn/9:
Line 184: Line 176:
=== ed11/10, ed17/10, ed19/10, ed23/10... ===
=== ed11/10, ed17/10, ed19/10, ed23/10... ===
A.k.a. "[[half-prime subgroup|tenth-prime subgroups]]".
A.k.a. "[[half-prime subgroup|tenth-prime subgroups]]".


To find BSGn/10:
To find BSGn/10:
Line 202: Line 193:
=== ed13/11, ed17/11, ed19/11, ed23/11... ===
=== ed13/11, ed17/11, ed19/11, ed23/11... ===
A.k.a. "[[half-prime subgroup|eleventh-prime subgroups]]".
A.k.a. "[[half-prime subgroup|eleventh-prime subgroups]]".


To find BSGn/11:
To find BSGn/11:
Line 219: Line 209:
=== ed13/12, ed17/12, ed29/12, ed23/12... ===
=== ed13/12, ed17/12, ed29/12, ed23/12... ===
A.k.a. "[[half-prime subgroup|twelfth-prime subgroups]]".
A.k.a. "[[half-prime subgroup|twelfth-prime subgroups]]".


To find BSGn/12:
To find BSGn/12:
Line 236: Line 225:
=== ed17/13, ed19/13, ed23/13, ed29/13... ===
=== ed17/13, ed19/13, ed23/13, ed29/13... ===
A.k.a. "[[half-prime subgroup|thirteenth-prime subgroups]]".
A.k.a. "[[half-prime subgroup|thirteenth-prime subgroups]]".


To find BSGn/13:
To find BSGn/13:
Line 252: Line 240:
=== ed17/14, ed19/14, ed23/14, ed29/14... ===
=== ed17/14, ed19/14, ed23/14, ed29/14... ===
A.k.a. "[[half-prime subgroup|fourteenth-prime subgroups]]".
A.k.a. "[[half-prime subgroup|fourteenth-prime subgroups]]".


To find BSGn/14:
To find BSGn/14:
Line 268: Line 255:
=== ed17/15, ed19/15, ed23/15, ed29/15... ===
=== ed17/15, ed19/15, ed23/15, ed29/15... ===
A.k.a. "[[half-prime subgroup|fifteenth-prime subgroups]]".
A.k.a. "[[half-prime subgroup|fifteenth-prime subgroups]]".


To find BSGn/15:
To find BSGn/15:
Line 322: Line 308:
# Remove all instances of m/1 where m is a prime factor of n
# Remove all instances of m/1 where m is a prime factor of n
# Remove all instances of m/1 where m is less than n's largest prime factor
# Remove all instances of m/1 where m is less than n's largest prime factor
# Replace all instances of m/1 with m/2
# Add n/2 to the start of the subgroup
# Add n/2 to the start of the subgroup
# In all instances a/b where a<b, double a
# In all instances a/b where a<b, double a
Line 336: Line 323:
=== ed4/3, ed8/3, ed10/3, ed14/3... ===
=== ed4/3, ed8/3, ed10/3, ed14/3... ===
A.k.a. "[[half-prime subgroup|third-prime subgroups]]".
A.k.a. "[[half-prime subgroup|third-prime subgroups]]".


To find BSGn/3:
To find BSGn/3:
Line 343: Line 329:
# Remove all instances of m/1 where m is a prime factor of n
# Remove all instances of m/1 where m is a prime factor of n
# Remove all instances of m/1 where m is less than n's largest prime factor
# Remove all instances of m/1 where m is less than n's largest prime factor
# Replace all instances of m/1 with m/3
# Add n/3 to the start of the subgroup
# Add n/3 to the start of the subgroup
# In all instances a/b where a<b, double a
# In all instances a/b where a<b, double a
Line 363: Line 350:
=== ed9/4, ed15/4, ed21/4, ed25/4... ===
=== ed9/4, ed15/4, ed21/4, ed25/4... ===
A.k.a. "[[half-prime subgroup|quarter-prime subgroups]]".
A.k.a. "[[half-prime subgroup|quarter-prime subgroups]]".


To find BSGn/4:
To find BSGn/4:
Line 370: Line 356:
# Remove all instances of m/1 where m is a prime factor of n
# Remove all instances of m/1 where m is a prime factor of n
# Remove all instances of m/1 where m is less than n's largest prime factor
# Remove all instances of m/1 where m is less than n's largest prime factor
# Replace all instances of m/1 with m/4
# Add n/4 to the start of the subgroup
# Add n/4 to the start of the subgroup
# In all instances a/b where a<b, double a
# In all instances a/b where a<b, double a
Line 384: Line 371:
=== ed6/5, ed8/5, ed9/5, ed12/5... ===
=== ed6/5, ed8/5, ed9/5, ed12/5... ===
A.k.a. "[[half-prime subgroup|fifth-prime subgroups]]".
A.k.a. "[[half-prime subgroup|fifth-prime subgroups]]".


To find BSGn/5:
To find BSGn/5:
Line 391: Line 377:
# Remove all instances of m/1 where m is a prime factor of n
# Remove all instances of m/1 where m is a prime factor of n
# Remove all instances of m/1 where m is less than n's largest prime factor
# Remove all instances of m/1 where m is less than n's largest prime factor
# Replace all instances of m/1 with m/5
# Add n/5 to the start of the subgroup
# Add n/5 to the start of the subgroup
# In all instances a/b where a<b, double a
# In all instances a/b where a<b, double a
Line 396: Line 383:


'''List:'''
'''List:'''
* The basal subgroup of '''[[ed6/5]]''' - - - BSG6/5 - - - is 6/5 . 5/5 . 7/5 . 11/5 . 13/5 . 17/5...
* The basal subgroup of '''[[ed6/5]]''' - - - BSG6/5 - - - is 6/5 . 7/5 . 11/5 . 13/5 . 17/5 . 19/5...
* The basal subgroup of '''[[ed8/5]]''' - - - BSG8/5 - - - is 8/5 . 5/5 . 7/5 . 11/5 . 13/5 . 17/5...
* The basal subgroup of '''[[ed8/5]]''' - - - BSG8/5 - - - is 8/5 . 7/5 . 11/5 . 13/5 . 17/5 . 19/5...
* The basal subgroup of '''[[ed9/5]]''' - - - BSG9/5 - - - is 9/5 . 5/5 . 7/5 . 11/5 . 13/5 . 17/5...
* The basal subgroup of '''[[ed9/5]]''' - - - BSG9/5 - - - is 9/5 . 7/5 . 11/5 . 13/5 . 17/5 . 19/5...
* The basal subgroup of '''[[ed12/5]]''' - - - BSG12/5 - - - is 12/5 . 5/5 . 7/5 . 11/5 . 13/5 . 17/5...
* The basal subgroup of '''[[ed12/5]]''' - - - BSG12/5 - - - is 12/5 . 7/5 . 11/5 . 13/5 . 17/5 . 19/5...
* The basal subgroup of '''[[ed14/5]]''' - - - BSG14/5 - - - is 14/5 . 11/5 . 13/5 . 17/5 . 19/5 . 23/5...
* The basal subgroup of '''[[ed14/5]]''' - - - BSG14/5 - - - is 14/5 . 11/5 . 13/5 . 17/5 . 19/5 . 23/5...
* The basal subgroup of '''[[ed16/5]]''' - - - BSG16/5 - - - is 16/5 . 3/5 . 5/5 . 7/5 . 11/5 . 13/5...
* The basal subgroup of '''[[ed16/5]]''' - - - BSG16/5 - - - is 16/5 . 3/5 . 7/5 . 11/5 . 13/5 . 17/5...
* The basal subgroup of '''[[ed18/5]]''' - - - BSG18/5 - - - is 18/5 . 5/5 . 7/5 . 11/5 . 13/5 . 17/5...
* The basal subgroup of '''[[ed18/5]]''' - - - BSG18/5 - - - is 18/5 . 7/5 . 11/5 . 13/5 . 17/5 . 19/5...
* The basal subgroup of '''[[ed21/5]]''' - - - BSG21/5 - - - is 21/5 . 11/5 . 13/5 . 17/5 . 19/5 . 23/5...
* The basal subgroup of '''[[ed21/5]]''' - - - BSG21/5 - - - is 21/5 . 11/5 . 13/5 . 17/5 . 19/5 . 23/5...
* The basal subgroup of '''[[ed22/5]]''' - - - BSG22/5 - - - is 22/5 . 13/5 . 17/5 . 19/5 . 23/5 . 29/5...
* The basal subgroup of '''[[ed22/5]]''' - - - BSG22/5 - - - is 22/5 . 13/5 . 17/5 . 19/5 . 23/5 . 29/5...
* The basal subgroup of '''[[ed24/5]]''' - - - BSG24/5 - - - is 24/5 . 5/5 . 7/5 . 11/5 . 13/5 . 17/5...
* The basal subgroup of '''[[ed24/5]]''' - - - BSG24/5 - - - is 24/5 . 7/5 . 11/5 . 13/5 . 17/5 . 19/5...
* The basal subgroup of '''[[ed26/5]]''' - - - BSG26/5 - - - is 26/5 . 17/5 . 19/5 . 23/5 . 29/5 . 31/5...
* The basal subgroup of '''[[ed26/5]]''' - - - BSG26/5 - - - is 26/5 . 17/5 . 19/5 . 23/5 . 29/5 . 31/5...
* The basal subgroup of '''[[ed27/5]]''' - - - BSG27/5 - - - is 27/5 . 5/5 . 7/5 . 11/5 . 13/5 . 17/5...
* The basal subgroup of '''[[ed27/5]]''' - - - BSG27/5 - - - is 27/5 . 7/5 . 11/5 . 13/5 . 17/5 . 19/5...
* The basal subgroup of '''[[ed28/5]]''' - - - BSG28/5 - - - is 28/5 . 11/5 . 13/5 . 17/5 . 19/5 . 23/5...
* The basal subgroup of '''[[ed28/5]]''' - - - BSG28/5 - - - is 28/5 . 11/5 . 13/5 . 17/5 . 19/5 . 23/5...
''and so on...''
''and so on...''
Line 413: Line 400:
=== ed35/6, ed55/6, ed65/6, ed77/6... ===
=== ed35/6, ed55/6, ed65/6, ed77/6... ===
A.k.a. "[[half-prime subgroup|sixth-prime subgroups]]".
A.k.a. "[[half-prime subgroup|sixth-prime subgroups]]".


To find BSGn/6:
To find BSGn/6:
Line 420: Line 406:
# Remove all instances of m/1 where m is a prime factor of n
# Remove all instances of m/1 where m is a prime factor of n
# Remove all instances of m/1 where m is less than n's largest prime factor
# Remove all instances of m/1 where m is less than n's largest prime factor
# Replace all instances of m/1 with m/6
# Add n/6 to the start of the subgroup
# Add n/6 to the start of the subgroup
# In all instances a/b where a<b, double a
# In all instances a/b where a<b, double a
Line 433: Line 420:
=== ed8/7, ed9/7, ed10/7, ed12/7... ===
=== ed8/7, ed9/7, ed10/7, ed12/7... ===
A.k.a. "[[half-prime subgroup|seventh-prime subgroups]]".
A.k.a. "[[half-prime subgroup|seventh-prime subgroups]]".


To find BSGn/7:
To find BSGn/7:
Line 440: Line 426:
# Remove all instances of m/1 where m is a prime factor of n
# Remove all instances of m/1 where m is a prime factor of n
# Remove all instances of m/1 where m is less than n's largest prime factor
# Remove all instances of m/1 where m is less than n's largest prime factor
# Replace all instances of m/1 with m/7
# Add n/7 to the start of the subgroup
# Add n/7 to the start of the subgroup
# In all instances a/b where a<b, double a
# In all instances a/b where a<b, double a
Line 463: Line 450:
=== ed9/8, ed15/8, ed21/8, ed25/8... ===
=== ed9/8, ed15/8, ed21/8, ed25/8... ===
A.k.a. "[[half-prime subgroup|eighth-prime subgroups]]".
A.k.a. "[[half-prime subgroup|eighth-prime subgroups]]".


To find BSGn/8:
To find BSGn/8:
Line 470: Line 456:
# Remove all instances of m/1 where m is a prime factor of n
# Remove all instances of m/1 where m is a prime factor of n
# Remove all instances of m/1 where m is less than n's largest prime factor
# Remove all instances of m/1 where m is less than n's largest prime factor
# Replace all instances of m/1 with m/8
# Add n/8 to the start of the subgroup
# Add n/8 to the start of the subgroup
# In all instances a/b where a<b, double a
# In all instances a/b where a<b, double a
Line 484: Line 471:
=== ed10/9, ed14/9, ed16/9, ed20/9... ===
=== ed10/9, ed14/9, ed16/9, ed20/9... ===
A.k.a. "[[half-prime subgroup|ninth-prime subgroups]]".
A.k.a. "[[half-prime subgroup|ninth-prime subgroups]]".


To find BSGn/9:
To find BSGn/9:
Line 491: Line 477:
# Remove all instances of m/1 where m is a prime factor of n
# Remove all instances of m/1 where m is a prime factor of n
# Remove all instances of m/1 where m is less than n's largest prime factor
# Remove all instances of m/1 where m is less than n's largest prime factor
# Replace all instances of m/1 with m/9
# Add n/9 to the start of the subgroup
# Add n/9 to the start of the subgroup
# In all instances a/b where a<b, double a
# In all instances a/b where a<b, double a
Line 508: Line 495:
=== ed21/10, ed27/10, ed33/10, ed39/10... ===
=== ed21/10, ed27/10, ed33/10, ed39/10... ===
A.k.a. "[[half-prime subgroup|tenth-prime subgroups]]".
A.k.a. "[[half-prime subgroup|tenth-prime subgroups]]".


To find BSGn/10:
To find BSGn/10:
Line 515: Line 501:
# Remove all instances of m/1 where m is a prime factor of n
# Remove all instances of m/1 where m is a prime factor of n
# Remove all instances of m/1 where m is less than n's largest prime factor
# Remove all instances of m/1 where m is less than n's largest prime factor
# Replace all instances of m/1 with m/10
# Add n/10 to the start of the subgroup
# Add n/10 to the start of the subgroup
# In all instances a/b where a<b, double a
# In all instances a/b where a<b, double a
Line 527: Line 514:


=== ed12/11, ed14/11, ed15/11, ed16/11... ===
=== ed12/11, ed14/11, ed15/11, ed16/11... ===
A.k.a. "[[half-prime subgroup|elevent-prime subgroups]]".
A.k.a. "[[half-prime subgroup|eleventh-prime subgroups]]".
 


To find BSGn/11:
To find BSGn/11:
Line 535: Line 521:
# Remove all instances of m/1 where m is a prime factor of n
# Remove all instances of m/1 where m is a prime factor of n
# Remove all instances of m/1 where m is less than n's largest prime factor
# Remove all instances of m/1 where m is less than n's largest prime factor
# Replace all instances of m/1 with m/11
# Add n/11 to the start of the subgroup
# Add n/11 to the start of the subgroup
# In all instances a/b where a<b, double a
# In all instances a/b where a<b, double a
Line 557: Line 544:
=== ed35/12, ed55/12, ed65/12, ed77/12... ===
=== ed35/12, ed55/12, ed65/12, ed77/12... ===
A.k.a. "[[half-prime subgroup|twelfth-prime subgroups]]".
A.k.a. "[[half-prime subgroup|twelfth-prime subgroups]]".


To find BSGn/12:
To find BSGn/12:
Line 564: Line 550:
# Remove all instances of m/1 where m is a prime factor of n
# Remove all instances of m/1 where m is a prime factor of n
# Remove all instances of m/1 where m is less than n's largest prime factor
# Remove all instances of m/1 where m is less than n's largest prime factor
# Replace all instances of m/1 with m/12
# Add n/12 to the start of the subgroup
# Add n/12 to the start of the subgroup
# In all instances a/b where a<b, double a
# In all instances a/b where a<b, double a
Line 581: Line 568:
# Remove all instances of m/1 where m is a prime factor of n
# Remove all instances of m/1 where m is a prime factor of n
# Remove all instances of m/1 where m is less than n's largest prime factor
# Remove all instances of m/1 where m is less than n's largest prime factor
# Replace all instances of m/1 with m/13
# Add n/13 to the start of the subgroup
# Add n/13 to the start of the subgroup
# In all instances a/b where a<b, double a
# In all instances a/b where a<b, double a
Line 606: Line 594:
# Remove all instances of m/1 where m is a prime factor of n
# Remove all instances of m/1 where m is a prime factor of n
# Remove all instances of m/1 where m is less than n's largest prime factor
# Remove all instances of m/1 where m is less than n's largest prime factor
# Replace all instances of m/1 with m/14
# Add n/14 to the start of the subgroup
# Add n/14 to the start of the subgroup
# In all instances a/b where a<b, double a
# In all instances a/b where a<b, double a
Line 623: Line 612:
# Remove all instances of m/1 where m is a prime factor of n
# Remove all instances of m/1 where m is a prime factor of n
# Remove all instances of m/1 where m is less than n's largest prime factor
# Remove all instances of m/1 where m is less than n's largest prime factor
# Replace all instances of m/1 with m/15
# Add n/15 to the start of the subgroup
# Add n/15 to the start of the subgroup
# In all instances a/b where a<b, double a
# In all instances a/b where a<b, double a

Latest revision as of 02:56, 7 May 2025

An basal subgroup[idiosyncratic term] is a subgroup which has a unique affiliation with one specific family of equal tunings.

It is built on top of the concept of a half-prime subgroup, so it is recommended to study half-prime subgroups first before exploring basal subgroups.

The basal subgroup for equal divisions of n/m is named BSGn/m[idiosyncratic term]. This makes it easy to refer to a specific BSG.


Example:

The basal subgroup of ed2/1 - - - BSG2/1 - - - is 2.3.5.7.11.13... a.k.a. 2/1 . 3/1 . 5/1 . 7/1 . 11/1 . 13/1...

Prime basal subgroups

ed3, ed5, ed7, ed11...

To find BSGn/1:

  1. Start with BSG2/1
  2. Remove all instances of m/1 where m<n

List:

  • The basal subgroup of ed3/1 - - - BSG3/1 - - - is 3/1 . 5/1 . 7/1 . 11/1 . 13/1 . 17/1...
  • The basal subgroup of ed5/1 - - - BSG5/1 - - - is 5/1 . 7/1 . 11/1 . 13/1 . 17/1 . 19/1...
  • The basal subgroup of ed7/1 - - - BSG7/1 - - - is 7/1 . 11/1 . 13/1 . 17/1 . 19/1 . 23/1...
  • The basal subgroup of ed11/1 - - - BSG11/1 - - - is 11/1 . 13/1 . 17/1 . 19/1 . 23/1 . 29/1...
  • The basal subgroup of ed13/1 - - - BSG13/1 - - - is 13/1 . 17/1 . 19/1 . 23/1 . 29/1 . 31/1...
  • The basal subgroup of ed17/1 - - - BSG17/1 - - - is 17/1 . 19/1 . 23/1 . 29/1 . 31/1 . 37/1...
  • The basal subgroup of ed19/1 - - - BSG19/1 - - - is 19/1 . 23/1 . 29/1 . 31/1 . 37/1 . 41/1...
  • The basal subgroup of ed23/1 - - - BSG23/1 - - - is 23/1 . 29/1 . 31/1 . 37/1 . 41/1 . 43/1...
  • The basal subgroup of ed29/1 - - - BSG29/1 - - - is 29/1 . 31/1 . 37/1 . 41/1 . 43/1 . 47/1...

and so on...

ed3/2, ed5/2, ed7/2, ed11/2...

A.k.a. "half-prime subgroups".

To find BSGn/2:

  1. Start with BSG2/1
  2. Remove all instances of m/1 where m<n
  3. Replace all instances of m/1 with m/2

List:

  • The basal subgroup of ed3/2 - - - BSG3/2 - - - is 3/2 . 5/2 . 7/2 . 11/2 . 13/2 . 17/2...
  • The basal subgroup of ed5/2 - - - BSG5/2 - - - is 5/2 . 7/2 . 11/2 . 13/2 . 17/2 . 19/2...
  • The basal subgroup of ed7/2 - - - BSG7/2 - - - is 7/2 . 11/2 . 13/2 . 17/2 . 19/2 . 23/2...
  • The basal subgroup of ed11/2 - - - BSG11/2 - - - is 11/2 . 13/2 . 17/2 . 19/2 . 23/2 . 29/2...
  • The basal subgroup of ed13/2 - - - BSG13/2 - - - is 13/2 . 17/2 . 19/2 . 23/2 . 29/2 . 31/2...
  • The basal subgroup of ed17/2 - - - BSG17/2 - - - is 17/2 . 19/2 . 23/2 . 29/2 . 31/2 . 37/2...
  • The basal subgroup of ed19/2 - - - BSG19/2 - - - is 19/2 . 23/2 . 29/2 . 31/2 . 37/2 . 41/2...
  • The basal subgroup of ed23/2 - - - BSG23/2 - - - is 23/2 . 29/2 . 31/2 . 37/2 . 41/2 . 43/2...
  • The basal subgroup of ed29/2 - - - BSG29/2 - - - is 29/2 . 31/2 . 37/2 . 41/2 . 43/2 . 47/2...

and so on...

ed5/3, ed7/3, ed11/3, ed17/3...

A.k.a. "third-prime subgroups".

To find BSGn/3:

  1. Start with BSG2/1
  2. Remove all instances of m/1 where m<n
  3. Replace all instances of m/1 with m/3

List:

  • The basal subgroup of ed5/3 - - - BSG5/3 - - - is 5/3 . 7/3 . 11/3 . 13/3 . 17/3 . 19/3...
  • The basal subgroup of ed7/3 - - - BSG7/3 - - - is 7/3 . 11/3 . 13/3 . 17/3 . 19/3 . 23/3...
  • The basal subgroup of ed11/3 - - - BSG11/3 - - - is 11/3 . 13/3 . 17/3 . 19/3 . 23/3 . 29.3...
  • The basal subgroup of ed13/3 - - - BSG13/3 - - - is 13/3 . 17/3 . 19/3 . 23/3 . 29/3 . 31/3...
  • The basal subgroup of ed17/3 - - - BSG17/3 - - - is 17/3 . 19/3 . 23/3 . 29/3 . 31/3 . 37/3...
  • The basal subgroup of ed19/3 - - - BSG19/3 - - - is 19/3 . 23/3 . 29/3 . 31/3 . 37/3 . 41/3...
  • The basal subgroup of ed23/3 - - - BSG23/3 - - - is 23/3 . 29/3 . 31/3 . 37/3 . 41/3 . 43/3...
  • The basal subgroup of ed29/3 - - - BSG29/3 - - - is 29/3 . 31/3 . 37/3 . 41/3 . 43/3 . 47/3...

and so on...

ed5/4, ed7/4, ed11/4, ed17/4...

A.k.a. "quarter-prime subgroups".

To find BSGn/4:

  1. Start with BSG2/1
  2. Remove all instances of m/1 where m<n
  3. Replace all instances of m/1 with m/4

List:

  • The basal subgroup of ed5/4 - - - BSG5/4 - - - is 5/4 . 7/4 . 11/4 . 13/4 . 17/4 . 19/4...
  • The basal subgroup of ed7/4 - - - BSG7/4 - - - is 7/4 . 11/4 . 13/4 . 17/4 . 19/4 . 23/4...
  • The basal subgroup of ed11/4 - - - BSG11/4 - - - is 11/4 . 13/4 . 17/4 . 19/4 . 23/4 . 29/4...
  • The basal subgroup of ed13/4 - - - BSG13/4 - - - is 13/4 . 17/4 . 19/4 . 23/4 . 29/4 . 31/4...
  • The basal subgroup of ed17/4 - - - BSG17/4 - - - is 17/4 . 19/4 . 23/4 . 29/4 . 31/4 . 37/4...
  • The basal subgroup of ed19/4 - - - BSG19/4 - - - is 19/4 . 23/4 . 29/4 . 31/4 . 37/4 . 41/4...
  • The basal subgroup of ed23/4 - - - BSG23/4 - - - is 23/4 . 29/4 . 31/4 . 37/4 . 41/4 . 43/4...
  • The basal subgroup of ed29/4 - - - BSG29/4 - - - is 29/4 . 31/4 . 37/4 . 41/4 . 43/4 . 47/4...

and so on...

ed7/5, ed11/5, ed17/5, ed19/5...

A.k.a. "fifth-prime subgroups".

To find BSGn/5:

  1. Start with BSG2/1
  2. Remove all instances of m/1 where m<n
  3. Replace all instances of m/1 with m/5

List:

  • The basal subgroup of ed7/5 - - - BSG7/5 - - - is 7/5 . 11/5 . 13/5 . 17/5 . 19/5 . 23/5...
  • The basal subgroup of ed11/5 - - - BSG11/5 - - - is 11/5 . 13/5 . 17/5 . 19/5 . 23/5 . 29/5...
  • The basal subgroup of ed13/5 - - - BSG13/5 - - - is 13/5 . 17/5 . 19/5 . 23/5 . 29/5 . 31/5...
  • The basal subgroup of ed17/5 - - - BSG17/5 - - - is 17/5 . 19/5 . 23/5 . 29/5 . 31/5 . 37/5...
  • The basal subgroup of ed19/5 - - - BSG19/5 - - - is 19/5 . 23/5 . 29/5 . 31/5 . 37/5 . 41/5...
  • The basal subgroup of ed23/5 - - - BSG23/5 - - - is 23/5 . 29/5 . 31/5 . 37/5 . 41/5 . 43/5...
  • The basal subgroup of ed29/5 - - - BSG29/5 - - - is 29/5 . 31/5 . 37/5 . 41/5 . 43/5 . 47/5...

and so on...

ed7/6, ed11/6, ed17/6, ed19/6...

A.k.a. "sixth-prime subgroups".

To find BSGn/6:

  1. Start with BSG2/1
  2. Remove all instances of m/1 where m<n
  3. Replace all instances of m/1 with m/6

List:

  • The basal subgroup of ed7/6 - - - BSG7/6 - - - is 7/6 . 11/6 . 13/6 . 17/6 . 19/6 . 23/6...
  • The basal subgroup of ed11/6 - - - BSG11/6 - - - is 11/6 . 13/6 . 17/6 . 19/6 . 23/6 . 29/6...
  • The basal subgroup of ed13/6 - - - BSG13/6 - - - is 13/6 . 17/6 . 19/6 . 23/6 . 29/6 . 31/6...
  • The basal subgroup of ed17/6 - - - BSG17/6 - - - is 17/6 . 19/6 . 23/6 . 29/6 . 31/6 . 37/6...
  • The basal subgroup of ed19/6 - - - BSG19/6 - - - is 19/6 . 23/6 . 29/6 . 31/6 . 37/6 . 41/6...
  • The basal subgroup of ed23/6 - - - BSG23/6 - - - is 23/6 . 29/6 . 31/6 . 37/6 . 41/6 . 43/6...
  • The basal subgroup of ed29/6 - - - BSG29/6 - - - is 29/6 . 31/6 . 37/6 . 41/6 . 43/6 . 47/6...

and so on...

ed11/7, ed17/7, ed19/7, ed23/7...

A.k.a. "seventh-prime subgroups".

To find BSGn/7:

  1. Start with BSG2/1
  2. Remove all instances of m/1 where m<n
  3. Replace all instances of m/1 with m/7

List:

  • The basal subgroup of ed11/7 - - - BSG11/7 - - - is 11/7 . 13/7 . 17/7 . 19/7 . 23/7 . 29/7...
  • The basal subgroup of ed13/7 - - - BSG13/7 - - - is 13/7 . 17/7 . 19/7 . 23/7 . 29/7 . 31/7...
  • The basal subgroup of ed17/7 - - - BSG17/7 - - - is 17/7 . 19/7 . 23/7 . 29/7 . 31/7 . 37/7...
  • The basal subgroup of ed19/7 - - - BSG19/7 - - - is 19/7 . 23/7 . 29/7 . 31/7 . 37/7 . 41/7...
  • The basal subgroup of ed23/7 - - - BSG23/7 - - - is 23/7 . 29/7 . 31/7 . 37/7 . 41/7 . 43/7...
  • The basal subgroup of ed29/7 - - - BSG29/7 - - - is 29/7 . 31/7 . 37/7 . 41/7 . 43/7 . 47/7...

and so on...

ed11/8, ed17/8, ed19/8, ed23/8...

A.k.a. "eighth-prime subgroups".

To find BSGn/8:

  1. Start with BSG2/1
  2. Remove all instances of m/1 where m<n
  3. Replace all instances of m/1 with m/8

List:

  • The basal subgroup of ed11/8 - - - BSG11/8 - - - is 11/8 . 13/8 . 17/8 . 19/8 . 23/8 . 29/8...
  • The basal subgroup of ed13/8 - - - BSG13/8 - - - is 13/8 . 17/8 . 19/8 . 23/8 . 29/8 . 31/8...
  • The basal subgroup of ed17/8 - - - BSG17/8 - - - is 17/8 . 19/8 . 23/8 . 29/8 . 31/8 . 37/8...
  • The basal subgroup of ed19/8 - - - BSG19/8 - - - is 19/8 . 23/8 . 29/8 . 31/8 . 37/8 . 41/8...
  • The basal subgroup of ed23/8 - - - BSG23/8 - - - is 23/8 . 29/8 . 31/8 . 37/8 . 41/8 . 43/8...
  • The basal subgroup of ed29/8 - - - BSG29/8 - - - is 29/8 . 31/8 . 37/8 . 41/8 . 43/8 . 47/8...

and so on...

ed11/9, ed17/9, ed19/9, ed23/9...

A.k.a. "ninth-prime subgroups".

To find BSGn/9:

  1. Start with BSG2/1
  2. Remove all instances of m/1 where m<n
  3. Replace all instances of m/1 with m/9

List:

  • The basal subgroup of ed11/9 - - - BSG11/9 - - - is 11/9 . 13/9 . 17/9 . 19/9 . 23/9 . 29/9...
  • The basal subgroup of ed13/9 - - - BSG13/9 - - - is 13/9 . 17/9 . 19/9 . 23/9 . 29/9 . 31/9...
  • The basal subgroup of ed17/9 - - - BSG17/9 - - - is 17/9 . 19/9 . 23/9 . 29/9 . 31/9 . 37/9...
  • The basal subgroup of ed19/9 - - - BSG19/9 - - - is 19/9 . 23/9 . 29/9 . 31/9 . 37/9 . 41/9...
  • The basal subgroup of ed23/9 - - - BSG23/9 - - - is 23/9 . 29/9 . 31/9 . 37/9 . 41/9 . 43/9...
  • The basal subgroup of ed29/9 - - - BSG29/9 - - - is 29/9 . 31/9 . 37/9 . 41/9 . 43/9 . 47/9...

and so on...

ed11/10, ed17/10, ed19/10, ed23/10...

A.k.a. "tenth-prime subgroups".

To find BSGn/10:

  1. Start with BSG2/1
  2. Remove all instances of m/1 where m<n
  3. Replace all instances of m/1 with m/10

List:

  • The basal subgroup of ed11/10 - - - BSG11/10 - - - is 11/10 . 13/10 . 17/10 . 19/10 . 23/10 . 29/10...
  • The basal subgroup of ed13/10 - - - BSG13/10 - - - is 13/10 . 17/10 . 19/10 . 23/10 . 29/10 . 31/10...
  • The basal subgroup of ed17/10 - - - BSG17/10 - - - is 17/10 . 19/10 . 23/10 . 29/10 . 31/10 . 37/10...
  • The basal subgroup of ed19/10 - - - BSG19/10 - - - is 19/10 . 23/10 . 29/10 . 31/10 . 37/10 . 41/10...
  • The basal subgroup of ed23/10 - - - BSG23/10 - - - is 23/10 . 29/10 . 31/10 . 37/10 . 41/10 . 43/10...
  • The basal subgroup of ed29/10 - - - BSG29/10 - - - is 29/10 . 31/10 . 37/10 . 41/10 . 43/10 . 47/10...

and so on...

ed13/11, ed17/11, ed19/11, ed23/11...

A.k.a. "eleventh-prime subgroups".

To find BSGn/11:

  1. Start with BSG2/1
  2. Remove all instances of m/1 where m<n
  3. Replace all instances of m/1 with m/11

List:

  • The basal subgroup of ed13/11 - - - BSG13/11 - - - is 13/11 . 17/11 . 19/11 . 23/11 . 29/11 . 31/11...
  • The basal subgroup of ed17/11 - - - BSG17/11 - - - is 17/11 . 19/11 . 23/11 . 29/11 . 31/11 . 37/11...
  • The basal subgroup of ed19/11 - - - BSG19/11 - - - is 19/11 . 23/11 . 29/11 . 31/11 . 37/11 . 41/11...
  • The basal subgroup of ed23/11 - - - BSG23/11 - - - is 23/11 . 29/11 . 31/11 . 37/11 . 41/11 . 43/11...
  • The basal subgroup of ed29/11 - - - BSG29/11 - - - is 29/11 . 31/11 . 37/11 . 41/11 . 43/11 . 47/11...

and so on...

ed13/12, ed17/12, ed29/12, ed23/12...

A.k.a. "twelfth-prime subgroups".

To find BSGn/12:

  1. Start with BSG2/1
  2. Remove all instances of m/1 where m<n
  3. Replace all instances of m/1 with m/12

List:

  • The basal subgroup of ed13/12 - - - BSG13/12 - - - is 13/12 . 17/12 . 19/12 . 23/12 . 29/12 . 31/12...
  • The basal subgroup of ed17/12 - - - BSG17/12 - - - is 17/12 . 19/12 . 23/12 . 29/12 . 31/12 . 37/12...
  • The basal subgroup of ed19/12 - - - BSG19/12 - - - is 19/12 . 23/12 . 29/12 . 31/12 . 37/12 . 41/12...
  • The basal subgroup of ed23/12 - - - BSG23/12 - - - is 23/12 . 29/12 . 31/12 . 37/12 . 41/12 . 43/12...
  • The basal subgroup of ed29/12 - - - BSG29/12 - - - is 29/12 . 31/12 . 37/12 . 41/12 . 43/12 . 47/12...

and so on...

ed17/13, ed19/13, ed23/13, ed29/13...

A.k.a. "thirteenth-prime subgroups".

To find BSGn/13:

  1. Start with BSG2/1
  2. Remove all instances of m/1 where m<n
  3. Replace all instances of m/1 with m/13

List:

  • The basal subgroup of ed17/13 - - - BSG17/13 - - - is 17/13 . 19/13 . 23/13 . 29/13 . 31/13 . 37/13...
  • The basal subgroup of ed19/13 - - - BSG19/13 - - - is 19/13 . 23/13 . 29/13 . 31/13 . 37/13 . 41/13...
  • The basal subgroup of ed23/13 - - - BSG23/13 - - - is 23/13 . 29/13 . 31/13 . 37/13 . 41/13 . 43/13...
  • The basal subgroup of ed29/13 - - - BSG29/13 - - - is 29/13 . 31/13 . 37/13 . 41/13 . 43/13 . 47/13...

and so on...

ed17/14, ed19/14, ed23/14, ed29/14...

A.k.a. "fourteenth-prime subgroups".

To find BSGn/14:

  1. Start with BSG2/1
  2. Remove all instances of m/1 where m<n
  3. Replace all instances of m/1 with m/14

List:

  • The basal subgroup of ed17/14 - - - BSG17/14 - - - is 17/14 . 19/14 . 23/14 . 29/14 . 31/14 . 37/14...
  • The basal subgroup of ed19/14 - - - BSG19/14 - - - is 19/14 . 23/14 . 29/14 . 31/14 . 37/14 . 41/14...
  • The basal subgroup of ed23/14 - - - BSG23/14 - - - is 23/14 . 29/14 . 31/14 . 37/14 . 41/14 . 43/14...
  • The basal subgroup of ed29/14 - - - BSG29/14 - - - is 29/14 . 31/14 . 37/14 . 41/14 . 43/14 . 47/14...

and so on...

ed17/15, ed19/15, ed23/15, ed29/15...

A.k.a. "fifteenth-prime subgroups".

To find BSGn/15:

  1. Start with BSG2/1
  2. Remove all instances of m/1 where m<n
  3. Replace all instances of m/1 with m/15

List:

  • The basal subgroup of ed17/15 - - - BSG17/15 - - - is 17/15 . 19/15 . 23/15 . 29/15 . 31/15 . 37/15...
  • The basal subgroup of ed19/15 - - - BSG19/15 - - - is 19/15 . 23/15 . 29/15 . 31/15 . 37/15 . 41/15...
  • The basal subgroup of ed23/15 - - - BSG23/15 - - - is 23/15 . 29/15 . 31/15 . 37/15 . 41/15 . 43/15...
  • The basal subgroup of ed29/15 - - - BSG29/15 - - - is 29/15 . 31/15 . 37/15 . 41/15 . 43/15 . 47/15...

and so on...

Composite basal subgroups

ed4, ed6, ed8, ed9...

To find BSGn/1:

  1. Start with BSG2/1
  2. Remove all instances of m/1 where m is a prime factor of n
  3. Remove all instances of m/1 where m is less than n's largest prime factor
  4. Add n/1 to the start of the subgroup

List:

  • The basal subgroup of ed4/1 - - - BSG4/1 - - - is 4/1 . 5/1 . 7/1 . 11/1 . 13/1 . 17/1...
  • The basal subgroup of ed6/1 - - - BSG6/1 - - - is 6/1 . 5/1 . 7/1 . 11/1 . 13/1 . 17/1...
  • The basal subgroup of ed8/1 - - - BSG8/1 - - - is 8/1 . 5/1 . 7/1 . 11/1 . 13/1 . 17/1...
  • The basal subgroup of ed9/1 - - - BSG9/1 - - - is 9/1 . 5/1 . 7/1 . 11/1 . 13/1 . 17/1...
  • The basal subgroup of ed10/1 - - - BSG10/1 - - - is 10/1 . 7/1 . 11/1 . 13/1 . 17/1 . 19/1...
  • The basal subgroup of ed12/1 - - - BSG12/1 - - - is 12/1 . 5/1 . 7/1 . 11/1 . 13/1 . 17/1...
  • The basal subgroup of ed14/1 - - - BSG14/1 - - - is 14/1 . 11/1 . 13/1 . 17/1 . 19/1 . 23/1...
  • The basal subgroup of ed15/1 - - - BSG15/1 - - - is 15/1 . 7/1 . 11/1 . 13/1 . 17/1 . 19/1...
  • The basal subgroup of ed16/1 - - - BSG16/1 - - - is 16/1 . 3/1 . 5/1 . 7/1 . 11/1 . 13/1...
  • The basal subgroup of ed18/1 - - - BSG18/1 - - - is 18/1 . 5/1 . 7/1 . 11/1 . 13/1 . 17/1...
  • The basal subgroup of ed20/1 - - - BSG20/1 - - - is 20/1 . 7/1 . 11/1 . 13/1 . 17/1 . 19/1...
  • The basal subgroup of ed21/1 - - - BSG21/1 - - - is 21/1 . 11/1 . 13/1 . 17/1 . 19/1 . 23/1...
  • The basal subgroup of ed22/1 - - - BSG22/1 - - - is 22/1 . 13/1 . 17/1 . 19/1 . 23/1 . 29/1...
  • The basal subgroup of ed24/1 - - - BSG24/1 - - - is 24/1 . 5/1 . 7/1 . 11/1 . 13/1 . 17/1...
  • The basal subgroup of ed25/1 - - - BSG25/1 - - - is 25/1 . 7/1 . 11/1 . 13/1 . 17/1 . 19/1...
  • The basal subgroup of ed26/1 - - - BSG26/1 - - - is 26/1 . 17/1 . 19/1 . 23/1 . 29/1 . 31/1...
  • The basal subgroup of ed27/1 - - - BSG27/1 - - - is 27/1 . 5/1 . 7/1 . 11/1 . 13/1 . 17/1...
  • The basal subgroup of ed28/1 - - - BSG28/1 - - - is 28/1 . 11/1 . 13/1 . 17/1 . 19/1 . 23/1...
  • The basal subgroup of ed30/1 - - - BSG30/1 - - - is 30/1 . 7/1 . 11/1 . 13/1 . 17/1 . 19/1 ...

and so on...

ed9/2, ed15/2, ed21/2, ed25/2...

A.k.a. "half-prime subgroups".


To find BSGn/2:

  1. Start with BSG2/1
  2. Remove all instances of m/1 where m shares a prime factor with 2
  3. Remove all instances of m/1 where m is a prime factor of n
  4. Remove all instances of m/1 where m is less than n's largest prime factor
  5. Replace all instances of m/1 with m/2
  6. Add n/2 to the start of the subgroup
  7. In all instances a/b where a<b, double a
  8. If a is still not bigger than b, keep doubling a until it becomes bigger than b

List:

  • The basal subgroup of ed9/2 - - - BSG9/2 - - - is 9/2 . 5/2 . 7/2 . 11/2 . 13/2 . 17/2...
  • The basal subgroup of ed15/2 - - - BSG15/2 - - - is 15/2 . 7/2 . 11/2 . 13/2 . 17/2 . 19/2...
  • The basal subgroup of ed21/2 - - - BSG21/2 - - - is 21/2 . 11/2 . 13/2 . 17/2 . 19/2 . 23/2...
  • The basal subgroup of ed25/2 - - - BSG25/2 - - - is 25/2 . 7/2 . 11/2 . 13/2 . 17/2 . 19/2...
  • The basal subgroup of ed27/2 - - - BSG27/2 - - - is 27/2 . 5/2 . 7/2 . 11/2 . 13/2 . 17/2...

and so on...

ed4/3, ed8/3, ed10/3, ed14/3...

A.k.a. "third-prime subgroups".

To find BSGn/3:

  1. Start with BSG2/1
  2. Remove all instances of m/1 where m shares a prime factor with 3
  3. Remove all instances of m/1 where m is a prime factor of n
  4. Remove all instances of m/1 where m is less than n's largest prime factor
  5. Replace all instances of m/1 with m/3
  6. Add n/3 to the start of the subgroup
  7. In all instances a/b where a<b, double a
  8. If a is still not bigger than b, keep doubling a until it becomes bigger than b

List:

  • The basal subgroup of ed4/3 - - - BSG4/3 - - - is 4/3 . 5/3 . 7/3 . 11/3 . 13/3 . 17/3...
  • The basal subgroup of ed8/3 - - - BSG8/3 - - - is 8/3 . 5/3 . 7/3 . 11/3 . 13/3 . 17/3...
  • The basal subgroup of ed10/3 - - - BSG10/3 - - - is 10/3 . 7/3 . 11/3 . 13/3 . 17/3 . 19/3...
  • The basal subgroup of ed14/3 - - - BSG14/3 - - - is 14/3 . 11/3 . 13/3 . 17/3 . 19/3 . 23/3...
  • The basal subgroup of ed16/3 - - - BSG16/3 - - - is 16/3 . 3/3 . 5/3 . 7/3 . 11/3 . 13/3...
  • The basal subgroup of ed18/3 - - - BSG18/3 - - - is 18/3 . 5/3 . 7/3 . 11/3 . 13/3 . 17/3...
  • The basal subgroup of ed20/3 - - - BSG20/3 - - - is 20/3 . 7/3 . 11/3 . 13/3 . 17/3 . 19/3...
  • The basal subgroup of ed22/3 - - - BSG22/3 - - - is 22/3 . 13/3 . 17/3 . 19/3 . 23/3 . 29/3...
  • The basal subgroup of ed25/3 - - - BSG25/3 - - - is 25/3 . 7/3 . 11/3 . 13/3 . 17/3 . 19/3...
  • The basal subgroup of ed26/3 - - - BSG26/3 - - - is 26/3 . 17/3 . 19/3 . 23/3 . 29/3 . 31/3...
  • The basal subgroup of ed28/3 - - - BSG28/3 - - - is 28/3 . 11/3 . 13/3 . 17/3 . 19/3 . 23/3...

and so on...

ed9/4, ed15/4, ed21/4, ed25/4...

A.k.a. "quarter-prime subgroups".

To find BSGn/4:

  1. Start with BSG2/1
  2. Remove all instances of m/1 where m shares a prime factor with 4
  3. Remove all instances of m/1 where m is a prime factor of n
  4. Remove all instances of m/1 where m is less than n's largest prime factor
  5. Replace all instances of m/1 with m/4
  6. Add n/4 to the start of the subgroup
  7. In all instances a/b where a<b, double a
  8. If a is still not bigger than b, keep doubling a until it becomes bigger than b

List:

  • The basal subgroup of ed9/4 - - - BSG9/4 - - - is 9/4 . 5/4 . 7/4 . 11/4 . 13/4 . 17/4...
  • The basal subgroup of ed15/4 - - - BSG15/4 - - - is 15/4 . 7/4 . 11/4 . 13/4 . 17/4 . 19/4...
  • The basal subgroup of ed21/4 - - - BSG21/4 - - - is 21/4 . 11/4 . 13/4 . 17/4 . 19/4 . 23/4...
  • The basal subgroup of ed25/4 - - - BSG25/4 - - - is 25/4 . 7/4 . 11/4 . 13/4 . 17/4 . 19/4...
  • The basal subgroup of ed27/4 - - - BSG27/4 - - - is 27/4 . 5/4 . 7/4 . 11/4 . 13/4 . 17/4...

and so on...

ed6/5, ed8/5, ed9/5, ed12/5...

A.k.a. "fifth-prime subgroups".

To find BSGn/5:

  1. Start with BSG2/1
  2. Remove all instances of m/1 where m shares a prime factor with 5
  3. Remove all instances of m/1 where m is a prime factor of n
  4. Remove all instances of m/1 where m is less than n's largest prime factor
  5. Replace all instances of m/1 with m/5
  6. Add n/5 to the start of the subgroup
  7. In all instances a/b where a<b, double a
  8. If a is still not bigger than b, keep doubling a until it becomes bigger than b

List:

  • The basal subgroup of ed6/5 - - - BSG6/5 - - - is 6/5 . 7/5 . 11/5 . 13/5 . 17/5 . 19/5...
  • The basal subgroup of ed8/5 - - - BSG8/5 - - - is 8/5 . 7/5 . 11/5 . 13/5 . 17/5 . 19/5...
  • The basal subgroup of ed9/5 - - - BSG9/5 - - - is 9/5 . 7/5 . 11/5 . 13/5 . 17/5 . 19/5...
  • The basal subgroup of ed12/5 - - - BSG12/5 - - - is 12/5 . 7/5 . 11/5 . 13/5 . 17/5 . 19/5...
  • The basal subgroup of ed14/5 - - - BSG14/5 - - - is 14/5 . 11/5 . 13/5 . 17/5 . 19/5 . 23/5...
  • The basal subgroup of ed16/5 - - - BSG16/5 - - - is 16/5 . 3/5 . 7/5 . 11/5 . 13/5 . 17/5...
  • The basal subgroup of ed18/5 - - - BSG18/5 - - - is 18/5 . 7/5 . 11/5 . 13/5 . 17/5 . 19/5...
  • The basal subgroup of ed21/5 - - - BSG21/5 - - - is 21/5 . 11/5 . 13/5 . 17/5 . 19/5 . 23/5...
  • The basal subgroup of ed22/5 - - - BSG22/5 - - - is 22/5 . 13/5 . 17/5 . 19/5 . 23/5 . 29/5...
  • The basal subgroup of ed24/5 - - - BSG24/5 - - - is 24/5 . 7/5 . 11/5 . 13/5 . 17/5 . 19/5...
  • The basal subgroup of ed26/5 - - - BSG26/5 - - - is 26/5 . 17/5 . 19/5 . 23/5 . 29/5 . 31/5...
  • The basal subgroup of ed27/5 - - - BSG27/5 - - - is 27/5 . 7/5 . 11/5 . 13/5 . 17/5 . 19/5...
  • The basal subgroup of ed28/5 - - - BSG28/5 - - - is 28/5 . 11/5 . 13/5 . 17/5 . 19/5 . 23/5...

and so on...

ed35/6, ed55/6, ed65/6, ed77/6...

A.k.a. "sixth-prime subgroups".

To find BSGn/6:

  1. Start with BSG2/1
  2. Remove all instances of m/1 where m shares a prime factor with 6
  3. Remove all instances of m/1 where m is a prime factor of n
  4. Remove all instances of m/1 where m is less than n's largest prime factor
  5. Replace all instances of m/1 with m/6
  6. Add n/6 to the start of the subgroup
  7. In all instances a/b where a<b, double a
  8. If a is still not bigger than b, keep doubling a until it becomes bigger than b

List:

  • The basal subgroup of ed35/6 - - - BSG35/6 - - - is 35/6 . 11/6 . 13/6 . 17/6 . 19/6 . 23/6...
  • The basal subgroup of ed55/6 - - - BSG55/6 - - - is 55/6 . 13/6 . 17/6 . 19/6 . 23/6 . 29/6...
  • The basal subgroup of ed65/6 - - - BSG65/6 - - - is 65/6 . 17/6 . 19/6 . 23/6 . 29/6 . 31/6...
  • The basal subgroup of ed77/6 - - - BSG77/6 - - - is 77/6 . 13/6 . 17/6 . 19/6 . 23/6 . 29/6...

and so on...

ed8/7, ed9/7, ed10/7, ed12/7...

A.k.a. "seventh-prime subgroups".

To find BSGn/7:

  1. Start with BSG2/1
  2. Remove all instances of m/1 where m shares a prime factor with 7
  3. Remove all instances of m/1 where m is a prime factor of n
  4. Remove all instances of m/1 where m is less than n's largest prime factor
  5. Replace all instances of m/1 with m/7
  6. Add n/7 to the start of the subgroup
  7. In all instances a/b where a<b, double a
  8. If a is still not bigger than b, keep doubling a until it becomes bigger than b

List:

  • The basal subgroup of ed8/7 - - - BSG8/7 - - - is 8/7 . 10/7 . 11/7 . 13/7 . 17/7 . 19/7...
  • The basal subgroup of ed9/7 - - - BSG9/7 - - - is 9/7 . 10/7 . 11/7 . 13/7 . 17/7 . 19/7...
  • The basal subgroup of ed10/7 - - - BSG10/7 - - - is 10/7 . 11/7 . 13/7 . 17/7 . 19/7 . 23/7...
  • The basal subgroup of ed12/7 - - - BSG12/7 - - - is 12/7 . 10/7 . 11/7 . 13/7 . 17/7 . 19/7...
  • The basal subgroup of ed15/7 - - - BSG15/7 - - - is 15/7 . 11/7 . 13/7 . 17/7 . 19/7 . 23/7...
  • The basal subgroup of ed16/7 - - - BSG16/7 - - - is 16/7 . 12/7 . 10/7 . 11/7 . 13/7 . 17/7...
  • The basal subgroup of ed18/7 - - - BSG18/7 - - - is 18/7 . 10/7 . 11/7 . 13/7 . 17/7 . 19/7...
  • The basal subgroup of ed20/7 - - - BSG20/7 - - - is 20/7 . 11/7 . 13/7 . 17/7 . 19/7 . 23/7...
  • The basal subgroup of ed22/7 - - - BSG22/7 - - - is 22/7 . 13/7 . 17/7 . 19/7 . 23/7 . 29/7...
  • The basal subgroup of ed24/7 - - - BSG24/7 - - - is 24/7 . 10/7 . 11/7 . 13/7 . 17/7 . 19/7...
  • The basal subgroup of ed25/7 - - - BSG25/7 - - - is 25/7 . 11/7 . 13/7 . 17/7 . 19/7 . 23/7...
  • The basal subgroup of ed26/7 - - - BSG26/7 - - - is 26/7 . 17/7 . 19/7 . 23/7 . 29/7 . 31/7...
  • The basal subgroup of ed27/7 - - - BSG27/7 - - - is 27/7 . 10/7 . 11/7 . 13/7 . 17/7 . 19/7...
  • The basal subgroup of ed30/7 - - - BSG30/7 - - - is 30/7 . 11/7 . 13/7 . 17/7 . 19/7 . 23/7...

and so on...

ed9/8, ed15/8, ed21/8, ed25/8...

A.k.a. "eighth-prime subgroups".

To find BSGn/8:

  1. Start with BSG2/1
  2. Remove all instances of m/1 where m shares a prime factor with 8
  3. Remove all instances of m/1 where m is a prime factor of n
  4. Remove all instances of m/1 where m is less than n's largest prime factor
  5. Replace all instances of m/1 with m/8
  6. Add n/8 to the start of the subgroup
  7. In all instances a/b where a<b, double a
  8. If a is still not bigger than b, keep doubling a until it becomes bigger than b

List:

  • The basal subgroup of ed9/8 - - - BSG9/8 - - - is 9/8 . 10/8 (ie 5/4) . 7/8 . 11/8 . 13/8 . 17/8...
  • The basal subgroup of ed15/8 - - - BSG15/8 - - - is 15/8 . 14/8 (ie 7/4) . 11/8 . 13/8 . 17/8 . 19/8...
  • The basal subgroup of ed21/8 - - - BSG21/8 - - - is 21/8 . 11/8 . 13/8 . 17/8 . 19/8 . 23/8..
  • The basal subgroup of ed25/8 - - - BSG25/8 - - - is 25/8 . 14/8 (ie 7/4) . 11/8 . 13/8 . 17/8 . 19/8...
  • The basal subgroup of ed27/8 - - - BSG27/8 - - - is 27/8 . 10/8 (ie 5/4) . 7/8 . 11/8 . 13/8 . 17/8...

and so on...

ed10/9, ed14/9, ed16/9, ed20/9...

A.k.a. "ninth-prime subgroups".

To find BSGn/9:

  1. Start with BSG2/1
  2. Remove all instances of m/1 where m shares a prime factor with 9
  3. Remove all instances of m/1 where m is a prime factor of n
  4. Remove all instances of m/1 where m is less than n's largest prime factor
  5. Replace all instances of m/1 with m/9
  6. Add n/9 to the start of the subgroup
  7. In all instances a/b where a<b, double a
  8. If a is still not bigger than b, keep doubling a until it becomes bigger than b

List:

  • The basal subgroup of ed10/9 - - - BSG10/9 - - - is 10/9 . 14/9 . 11/9 . 13/9 . 17/9 . 19/9...
  • The basal subgroup of ed14/9 - - - BSG14/9 - - - is 14/9 . 11/9 . 13/9 . 17/9 . 19/9 . 23/9...
  • The basal subgroup of ed16/9 - - - BSG16/9 - - - is 16/9 . 10/9 . 7/9 . 11/9 . 13/9 . 17/9...
  • The basal subgroup of ed20/9 - - - BSG20/9 - - - is 20/9 . 14/9 . 11/9 . 13/9 . 17/9 . 19/9...
  • The basal subgroup of ed22/9 - - - BSG22/9 - - - is 22/9 . 13/9 . 17/9 . 19/9 . 23/9 . 29/9...
  • The basal subgroup of ed25/9 - - - BSG25/9 - - - is 25/9 . 14/9 . 11/9 . 13/9 . 17/9 . 19/9...
  • The basal subgroup of ed26/9 - - - BSG26/9 - - - is 26/9 . 17/9 . 19/9 . 23/9 . 29/9 . 31/9...
  • The basal subgroup of ed28/9 - - - BSG28/9 - - - is 28/9 . 11/9 . 13/9 . 17/9 . 19/9 . 23/9...

and so on...

ed21/10, ed27/10, ed33/10, ed39/10...

A.k.a. "tenth-prime subgroups".

To find BSGn/10:

  1. Start with BSG2/1
  2. Remove all instances of m/1 where m shares a prime factor with 10
  3. Remove all instances of m/1 where m is a prime factor of n
  4. Remove all instances of m/1 where m is less than n's largest prime factor
  5. Replace all instances of m/1 with m/10
  6. Add n/10 to the start of the subgroup
  7. In all instances a/b where a<b, double a
  8. If a is still not bigger than b, keep doubling a until it becomes bigger than b

List:

  • The basal subgroup of ed21/10 - - - BSG21/10 - - - is 21/10 . 11/10 . 13/10 . 17/10 . 19/10 . 23/10...
  • The basal subgroup of ed27/10 - - - BSG27/10 - - - is 27/10 . 14/10 (ie 7/5) . 11/10 . 13/10 . 17/10 . 19/10...
  • The basal subgroup of ed33/10 - - - BSG33/10 - - - is 33/10 . 13/10 . 17/10 . 19/10 . 23/10 . 29/10...
  • The basal subgroup of ed39/10 - - - BSG39/10 - - - is 39/10 . 17/10 . 19/10 . 23/10 . 29/10 . 31/10...

and so on...

ed12/11, ed14/11, ed15/11, ed16/11...

A.k.a. "eleventh-prime subgroups".

To find BSGn/11:

  1. Start with BSG2/1
  2. Remove all instances of m/1 where m shares a prime factor with 11
  3. Remove all instances of m/1 where m is a prime factor of n
  4. Remove all instances of m/1 where m is less than n's largest prime factor
  5. Replace all instances of m/1 with m/11
  6. Add n/11 to the start of the subgroup
  7. In all instances a/b where a<b, double a
  8. If a is still not bigger than b, keep doubling a until it becomes bigger than b

List:

  • The basal subgroup of ed12/11 - - - BSG12/11 - - - is 12/11 . 20/11 . 14/11 . 13/11 . 17/11 . 19/11...
  • The basal subgroup of ed14/11 - - - BSG14/11 - - - is 14/11 . 13/11 . 17/11 . 19/11 . 23/11 . 29/11...
  • The basal subgroup of ed15/11 - - - BSG15/11 - - - is 15/11 . 14/11 . 13/11 . 17/11 . 19/11 . 23/11...
  • The basal subgroup of ed16/11 - - - BSG16/11 - - - is 16/11 . 12/11 . 20/11 . 14/11 . 13/11 . 17/11...
  • The basal subgroup of ed18/11 - - - BSG18/11 - - - is 18/11 . 20/11 . 14/11 . 13/11 . 17/11 . 19/11...
  • The basal subgroup of ed20/11 - - - BSG20/11 - - - is 20/11 . 14/11 . 13/11 . 17/11 . 19/11 . 23/11...
  • The basal subgroup of ed21/11 - - - BSG21/11 - - - is 21/11 . 13/11 . 17/11 . 19/11 . 23/11 . 29/11...
  • The basal subgroup of ed24/11 - - - BSG24/11 - - - is 24/11 . 20/11 . 14/11 . 13/11 . 17/11 . 19/11...
  • The basal subgroup of ed25/11 - - - BSG25/11 - - - is 25/11 . 14/11 . 13/11 . 17/11 . 19/11 . 23/11...
  • The basal subgroup of ed26/11 - - - BSG26/11 - - - is 26/11 . 17/11 . 19/11 . 23/11 . 29/11 . 31/11...
  • The basal subgroup of ed27/11 - - - BSG27/11 - - - is 27/11 . 20/11 . 14/11 . 13/11 . 17/11 . 19/11...
  • The basal subgroup of ed28/11 - - - BSG28/11 - - - is 28/11 . 13/11 . 17/11 . 19/11 . 23/11 . 29/11...
  • The basal subgroup of ed30/11 - - - BSG30/11 - - - is 30/11 . 14/11 . 13/11 . 17/11 . 19/11 . 23/11...

and so on...

ed35/12, ed55/12, ed65/12, ed77/12...

A.k.a. "twelfth-prime subgroups".

To find BSGn/12:

  1. Start with BSG2/1
  2. Remove all instances of m/1 where m shares a prime factor with 12
  3. Remove all instances of m/1 where m is a prime factor of n
  4. Remove all instances of m/1 where m is less than n's largest prime factor
  5. Replace all instances of m/1 with m/12
  6. Add n/12 to the start of the subgroup
  7. In all instances a/b where a<b, double a
  8. If a is still not bigger than b, keep doubling a until it becomes bigger than b

List:

  • The basal subgroup of ed35/12 - - - BSG35/12 - - - is 35/12 . 22/12 (ie 11/6) . 13/12 . 17/12 . 19/12 . 23/12...
  • The basal subgroup of ed55/12 - - - BSG55/12 - - - is 55/12 . 13/12 . 17/12 . 19/12 . 23/12 . 29/12...
  • The basal subgroup of ed65/12 - - - BSG65/12 - - - is 65/12 . 17/12 . 19/12 . 23/12 . 29/12 . 31/12...
  • The basal subgroup of ed77/12 - - - BSG77/12 - - - is 77/12 . 13/12 . 17/12 . 19/12 . 23/12 . 29/12...

and so on...

ed14/13, ed15/13, ed16/13, ed18/13...

To find BSGn/13:

  1. Start with BSG2/1
  2. Remove all instances of m/1 where m shares a prime factor with 13
  3. Remove all instances of m/1 where m is a prime factor of n
  4. Remove all instances of m/1 where m is less than n's largest prime factor
  5. Replace all instances of m/1 with m/13
  6. Add n/13 to the start of the subgroup
  7. In all instances a/b where a<b, double a
  8. If a is still not bigger than b, keep doubling a until it becomes bigger than b

List:

  • The basal subgroup of ed14/13 - - - BSG14/13 - - - is 14/13 . 22/13 . 17/13 . 19/13 . 23/13 . 29/13...
  • The basal subgroup of ed15/13 - - - BSG15/13 - - - is 15/13 . 14/13 . 22/13 . 13/13 . 17/13 . 19/13...
  • The basal subgroup of ed16/13 - - - BSG16/13 - - - is 16/13 . 24/13 . 20/13 . 14/13 . 22/13 . 17/13...
  • The basal subgroup of ed18/13 - - - BSG18/13 - - - is 18/13 . 20/13 . 14/13 . 22/13 . 17/13 . 19/13...
  • The basal subgroup of ed20/13 - - - BSG20/13 - - - is 20/13 . 14/13 . 22/13 . 17/13 . 19/13 . 23/13...
  • The basal subgroup of ed21/13 - - - BSG21/13 - - - is 21/13 . 22/13 . 17/13 . 19/13 . 23/13 . 29/13...
  • The basal subgroup of ed22/13 - - - BSG22/13 - - - is 22/13 . 17/13 . 19/13 . 23/13 . 29/13 . 31/13...
  • The basal subgroup of ed24/13 - - - BSG24/13 - - - is 24/13 . 20/13 . 14/13 . 22/13 . 17/13 . 19/13...
  • The basal subgroup of ed25/13 - - - BSG25/13 - - - is 25/13 . 14/13 . 22/13 . 17/13 . 19/13 . 23/13...
  • The basal subgroup of ed27/13 - - - BSG27/13 - - - is 27/13 . 20/13 . 14/13 . 22/13 . 17/13 . 19/13...
  • The basal subgroup of ed28/13 - - - BSG28/13 - - - is 28/13 . 22/13 . 17/13 . 19/13 . 23/13 . 29/13...
  • The basal subgroup of ed30/13 - - - BSG30/13 - - - is 30/13 . 14/13 . 22/13 . 17/13 . 19/13 . 23/13...

and so on...

ed15/14, ed25/14, ed27/14, ed33/14...

To find BSGn/14:

  1. Start with BSG2/1
  2. Remove all instances of m/1 where m shares a prime factor with 14
  3. Remove all instances of m/1 where m is a prime factor of n
  4. Remove all instances of m/1 where m is less than n's largest prime factor
  5. Replace all instances of m/1 with m/14
  6. Add n/14 to the start of the subgroup
  7. In all instances a/b where a<b, double a
  8. If a is still not bigger than b, keep doubling a until it becomes bigger than b

List:

  • The basal subgroup of ed15/14 - - - BSG15/14 - - - is 15/14 . 22/14 (ie 11/7) . 26/14 (ie 13/7) . 17/14 . 19/14 . 23/14...
  • The basal subgroup of ed25/14 - - - BSG25/14 - - - is 25/14 . 11/14 . 26/14 (ie 13/7) . 17/14 . 19/14 . 23/14...
  • The basal subgroup of ed27/14 - - - BSG27/14 - - - is 27/14 . 20/14 (ie 10/7) . 11/14 . 13/14 . 17/14 . 19/14...
  • The basal subgroup of ed33/14 - - - BSG33/14 - - - is 33/14 . 26/14 (ie 13/7) . 17/14 . 19/14 . 23/14 . 29/14...

and so on...

ed16/15, ed22/15, ed26/15, ed28/15...

To find BSGn/15:

  1. Start with BSG2/1
  2. Remove all instances of m/1 where m shares a prime factor with 15
  3. Remove all instances of m/1 where m is a prime factor of n
  4. Remove all instances of m/1 where m is less than n's largest prime factor
  5. Replace all instances of m/1 with m/15
  6. Add n/15 to the start of the subgroup
  7. In all instances a/b where a<b, double a
  8. If a is still not bigger than b, keep doubling a until it becomes bigger than b

List:

  • The basal subgroup of ed16/15 - - - BSG16/15 - - - is 16/15 . 28/15 . 22/15 . 26/15...
  • The basal subgroup of ed22/15 - - - BSG22/15 - - - is 22/15 . 26/15 . 17/15 . 19/15 . 23/15 . 29/15...
  • The basal subgroup of ed26/15 - - - BSG26/15 - - - is 26/15 . 17/15 . 19/15 . 23/15 . 29/15 . 31/15...
  • The basal subgroup of ed28/15 - - - BSG28/15 - - - is 28/15 . 22/15 . 26/15 . 17/15 . 19/15 . 23/15...

and so on...

Use cases

Basal subgroups are most useful as starting points when beginning to explore an equal tuning. They give you a solid fundamental skeleton to start with, which you can then tweak and tinker with by adding and removing elements from the subgroup, or swapping them out for other ones.

Basal subgroups can also be used as a rough way to measure the "unusualness" of a subgroup in a given equal tuning.

If the subgroup is quite similar to the basal subgroup, then it is a to-be-expected subgroup. For example subgroups like 2.3.7.11 and 2.3.5.11 are very similar to BSG2/1 (2.3.5.7.11...) with slight modifications, so it is not unexpected to see them get used often in ed2/1s (edos).

However if the subgroup is quite different to the basal subgroup, then that means it is highly unusual (not better or worse necessarily, just more unexpected). So for example it would be quite strange to see a 2.53/10.111/43 subgroup get used in an ed2, because that is extremely far removed from BSG2/1.

Related concepts