21/13

Interval information
Ratio	21/13
Factorization	3 × 7 × 13-1
Monzo	[0 1 0 1 0 -1⟩
Size in cents	830.2532¢
Name	tridecimal supraminor sixth
FJS name	[math]\displaystyle{ \text{M6}^{7}_{13} }[/math]
Special properties	reduced
Tenney norm (log2 nd)	8.09276
Weil norm (log2 max(n, d))	8.78463
Wilson norm (sopfr(nd))	23
	https://en.xen.wiki/w/File:Ji-21-13-csound-foscil-220hz.mp3; [sound info]
	Open this interval in xen-calc

21/13, the tridecimal supraminor sixth, is ca. 830 cents in size. It has a very good approximation in 13edo.

See also