Calculated as the 36th root of 25 -- 36√25, or 2(5/36) -- an irrational proportion with the approximate ratio of 1 : 1.101056795, and an interval size of exactly 166 2/3 cents. It is the size of 5 degrees in the 36-edo (or 36-tET) scale, and of 10 degrees in the 72-edo (72-tET) scale.
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