Mersenne comma

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Mersenne commas are a series of commas of the form [math]\displaystyle{ \frac{2^n}/{2^n-1} }[/math].

Since Mersenne prime commas effectively set their own prime limit, they are of no interest to EDO theory. Therefore, this time Mersenne composite numbers enter the stage - sequence A135972 in OEIS.

Theory

Table of first Mersenne composite commas
Index Comma Prime

Subgroup

Monzo

(zeroes skipped)

Comments
4 16/15 2.3.5 [4 -1 -1⟩ Classic diatonic semitone.
6 64/63 2.3.7 [6 -2 -1⟩ Septimal comma.
8 256/255 2.3.5.17 [8 -1 -1 -1⟩ Septendecimal kleisma.
9 512/511 2.7.73 [9 -1 -1⟩
10 1024/1023 2.3.11.31 [10 -1 -1 -1⟩
11 2048/2047 2.23.89 [11 -1 -1⟩
12 4096/4095 2.3.5.7.13 [12 -2 -1 -1 -1⟩ Schismina.