20/9

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Interval information

Ratio	20/9
Factorization	22 × 3-2 × 5
Monzo	[2 -2 1⟩
Size in cents	1382.404¢
Name	Ptolemaic ninth
Color name	y9, yo 9th
FJS name	[math]\text{M9}^{5}[/math]
Tenney height (log2 nd)	7.49185
Weil height (log2 max(n, d))	8.64386
Wilson height (sopfr(nd))	15
Harmonic entropy (Shannon, [math]\sqrt{nd}[/math])	~4.22499 bits
open this interval in xen-calc

20/9, the Ptolemaic ninth; the ratio between the 20th and 9th harmonics; one octave above 10/9.