4/3

4/3 is the frequency ratio of the just perfect fourth. Its inversion is the perfect fifth, 3/2.

Interval information

Ratio	4/3
Factorization	22 × 3-1
Monzo	[2 -1⟩
Size in cents	498.045¢
Name	just perfect fourth
Color name	w4, wa 4th
FJS name	[math]\displaystyle{ \text{P4} }[/math]
Special properties	square superparticular, reduced, reduced subharmonic
Tenney norm (log2 nd)	3.58496
Weil norm (log2 max(n, d))	4
Wilson norm (sopfr(nd))	7
[sound info]
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See also Perfect fourth (Wikipedia)