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The Pythagorean or ditonic comma (about 23.460¢) is the interval 531441/524288 = |-19 12> (see monzo). It could also be called the 12-comma as it is the amount by which twelve fifths exceed seven octaves, or in other words (3/2)^12/2^7 and it also can be written as the ratio between the apotome and the Pythagorean minor second, (2187/2048)/(256/243). For EDOs up to 300, it is tempered out if and only if the EDO is a multiple of 12, and hence for instance by 24edo, 72edo and 84edo.

See: Gallery of Just Intervals, comma

Wikipedia article