28561/28560: Difference between revisions

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{{Infobox Interval
{{Infobox Interval
| Name = neuseisma
| Ratio = 28561/28560
| Comma = yes
| Comma = yes
| Name = Pisanoisma
| Color name = suquadtho-arugu 1sn
| Color name = suquadtho-arugu 1sn
}}
}}
'''28561/28560''', the '''neuseisma''', is an [[Unnoticeable comma|unnoticeable]] [[17-limit]] [[comma]] of about 0.06{{cent}}.  
'''28561/28560''' is an [[Unnoticeable comma|unnoticeable]] [[17-limit]] [[comma]] of about 0.06{{cent}}. It is a superparticular with a fourth power as its numerator, in this case 13<sup>4</sup> = 169<sup>2</sup> so that this comma is expressible as [[S-expression|S]]169 and as the difference between [[169/168]] and [[170/169]]. Its denominator decomposes as (13<sup>2</sup> - 1)(13<sup>2</sup> + 1), which, as 13 is a member of the Fibonacci sequence, by a property of that sequence is equal to 5*8*21*34, the product of the four nearest members of the sequence to 13. This is responsible for the comma belonging to a relatively low [[prime limit]] for the size of its numerator and denominator, though the same Fibonacci property also applies to the [[scintillisma]], S441 = S(21<sup>2</sup>). Therefore, this comma has been given the name of the '''pisanoisma''', in reference to Leonardo Pisano, the discoverer of the Fibonacci sequence.


== Commatic relations ==
== Commatic relations ==
This comma is the difference between
* [[169/168]] and [[170/169]]
It factors into
It factors into
* [[37180/37179]] and [[123201/123200]]
* [[37180/37179]] and [[123201/123200]]
* [[31213/31212]] and [[336141/336140]]
* [[31213/31212]] and [[336141/336140]]
== Temperaments ==
Tempering out this comma in the 17-limit results in the rank-6 '''neuseismic temperament''', or in the 2.3.5.7.13.17 subgroup, the rank-5 '''neuseic temperament'''.
== Etymology ==
This comma is named by [[User:BudjarnLambeth|Budjarn Lambeth]] in 2023, after Neuse Forest, North Carolina, which has a ZIP code of 28560.
[[Category:Neuseismic]]