31/27

Interval information

Ratio	31/27
Subgroup monzo	3.31 [-3 1⟩
Size in cents	239.1706¢
Names	(lesser) tricesimoprimal ultramajor second, (lesser) tricesimoprimal inframinor third
Color name	31o2, thiwo 2nd
FJS name	[math]\displaystyle{ \text{M2}^{31} }[/math]
Special properties	reduced
Tenney height (log2 nd)	9.70908
Weil height (log2 max(n, d))	9.90839
Wilson height (sopfr(nd))	40
Harmonic entropy (Shannon, [math]\displaystyle{ \sqrt{nd} }[/math])	~4.21409 bits
Open this interval in xen-calc

In 31-limit just intonation, 31/27 is either the tricesimoprimal ultramajor second or tricesimoprimal inframinor third. It is sharp of the Pythagorean major second (9/8) by 248/243, sharp of the septimal major second (8/7) by 217/216, and flat of the minor third (32/27) by 32/31.

Approximation

This interval is very accurately approximated by 1\5.

See also

• 54/31 – its octave complement
• 36/31 – its fourth complement