125/81

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Interval information
Ratio 125/81
Factorization 3-4 × 53
Monzo [0 -4 3⟩
Size in cents 751.1211 ¢
Names triptolemaic augmented fifth,
Trithagorean ultrafifth
Color name triyo 5th, y35
FJS name [math]\displaystyle{ \text{A5}^{5,5,5} }[/math]
Special properties reduced
Tenney norm (log2 nd) 13.3056
Weil norm (log2 max(n, d)) 13.9316
Wilson norm (sopfr(nd)) 27
Open this interval in xen-calc

The triptolemaic augmented fifth or Trithagorean ultrafifth, 125/81, is equal to 25/16 lowered by 81/80, or alternatively the Pythagorean minor sixth 128/81 lowered by 128/125. It also appears as a notable interval in the Trithagorean scale/3.5 subgroup, being the tritave-reduction of (5/3)3. It can be closely approximated by 17/11.

Approximation

Edo approximations for 125/81 (751.12 ¢)
≤ 80edo, relative error ≤ 10%
Edo Step size Cents (¢) Absolute error (¢) Relative error (%)
8 5\8 750.00 -1.12 -0.75
16 10\16 750.00 -1.12 -1.49
24 15\24 750.00 -1.12 -2.24
27 17\27 755.56 +4.43 +9.98
32 20\32 750.00 -1.12 -2.99
35 22\35 754.29 +3.16 +9.23
40 25\40 750.00 -1.12 -3.74
43 27\43 753.49 +2.37 +8.48
48 30\48 750.00 -1.12 -4.48
51 32\51 752.94 +1.82 +7.74
56 35\56 750.00 -1.12 -5.23
59 37\59 752.54 +1.42 +6.99
64 40\64 750.00 -1.12 -5.98
67 42\67 752.24 +1.12 +6.24
72 45\72 750.00 -1.12 -6.73
75 47\75 752.00 +0.88 +5.49
80 50\80 750.00 -1.12 -7.47