7777/7776

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Interval information

Ratio	7777/7776
Subgroup monzo	2.3.7.11.101 [-5 -5 1 1 1⟩
Size in cents	0.2226238¢
Name	pulsar comma
Color name	101o1oz2, Fifiwolozo comma
FJS name	[math]\displaystyle{ \text{d2}^{7,11,101} }[/math]
Special properties	superparticular, reduced
Tenney norm (log2 nd)	25.8498
Weil norm (log2 max(n, d))	25.85
Wilson norm (sopfr(nd))	144
Comma size	unnoticeable
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7777/7776, the pulsar comma or power-of-six repdigit comma is an unnoticeable comma of 0.223 cents, and it is a part of 101-limit just intonation.

The comma derives from the resemblance of a perfect power of 6, 7776, to a decimal repdigit number 7777. It is the difference between a stack of five 6/1's and 7, 11, and 101 harmonics stacked, or when octave-reduced, between 7/4, 11/8, and 101/64 and the Pythagorean major seventh, 243/128. It is also the difference between 404/243 and 128/77.

The name origin is the following: power-of-six repdigit – psr, which is the astronomical shortening for pulsars.

Temperaments

Some of the edos which support pulsar temperaments in its 2.3.7.11.101-subgroup patent vals are 135, 207, 342, 477, 836, 877, 971, 1012, and 1147.