The just intonation scale has 21 notes in the octave, but that's just for C major/ A minor. If you want to transpose to other keys you have to add more notes, for a total of 70, but that also lets you play in 6 major/ minor keys that you can't get with the 12 note scale. All 70 notes are given in a file on my website, starting with the basic 21, then adding those needed for 1 sharp or flat on the key signature, then 2, then 3, to 7, then the extra 6.

There is also a treatment there of all the normal 7, 6, and 5 notes scales and a click on to Jack Campin's website for an alternative treatment with many examples as ABCs.

File COMBCOD2.TXT now has over 5300 tunes codes in 166 total modes.