7921/7776

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Interval information

Ratio	7921/7776
Subgroup monzo	2.3.89 [-5 -5 2⟩
Size in cents	31.98523¢
Name	Attic comma
Color name	89oo1
FJS name	[math]\text{A1}^{89,89}[/math]
Special properties	reduced
Tenney height (log2 nd)	25.8763
Weil height (log2 max(n, d))	25.9029
Wilson height (sopfr(nd))	203
Harmonic entropy (Shannon, [math]\sqrt{nd}[/math])	~4.48592 bits
Comma size	medium
open this interval in xen-calc

7936/7921, a.k.a. the attic comma, is tempered out by the Floor temperament.

Tempering this comma on its own gives the attic temperament, a rank-2, 2.3.89 subgroup tuning.

Attic

Equal Temperament Mappings
2	3	89	
[ ⟨	7	11	45	]
⟨	17	27	110	] ⟩
 
Reduced Mapping
2	3	89	
[ ⟨	1	1	5	]
⟨	0	2	5	] ⟩
 
TE Generator Tunings (cents)
⟨1200.6258, 351.4507]
 
TE Step Tunings (cents)
⟨28.46792, 58.90296]
 
TE Tuning Map (cents)
⟨1200.626, 1903.527, 7760.382]
 
TE Mistunings (cents)
⟨0.626, 1.572, -10.498]

These calculations use inharmonic TE. Subgroup TE will not work because the basis is not a subgroup of the rational numbers or has a redundant entry or something else is wrong.
 
Complexity	0.519162
Adjusted Error	7.480760 cents
TE Error	1.155199 cents/octave
 
Unison Vector
[-5, -5, 2⟩ (7921:7776)