364/363, the gentle comma, is a 13-limit no-5 small comma measuring about 4.8 ¢. It is the amount by which an undecimal major third 14/11 and a tridecimal minor third 13/11 exceed a just perfect fifth 3/2.
In terms of commas, it is the difference between the following superparticular pairs:
- 91/90 and 121/120
- 243/242 and 729/728
- 325/324 and 3025/3024
- 351/350 and 9801/9800
- 352/351 and 10648/10647
It factors into the following superparticular pairs:
Not to mention some nonsuperparticular but useful relations:
Tempering out the gentle comma leads to a form of gentle temperament and enables gentle chords.