The intervals in major thirds tuning with twelve notes per octave are
laid out like this:
8/5 5/3 16/9 15/8
5/4 4/3 7/5 3/2
1/1 16/15 9/8 6/5
With nineteen notes per octave they look like:
48/25
14/9 8/5 5/3 12/7 16/9 15/8
5/4 9/7 4/3 7/5 10/7 3/2
1/1 25/24 16/15 9/8 7/6 6/5
and the original twelve intervals are no longer evenly spaced:
/
/ 8/5 5/3 / 16/9 15/8
5/4 / 4/3 7/5 / 3/2
1/1 / 16/15 9/8 / 6/5
With thirty-one notes per octave they look like:
88/45
14/9 8/5 13/8 5/3 12/7 7/4 16/9 11/6 15/8 48/25
5/4 9/7 13/10 4/3 11/8 7/5 10/7 16/11 3/2 20/13
1/1 45/44 25/24 16/15 12/11 9/8 8/7 7/6 6/5 16/13
and the previous nineteen intervals are no longer evenly spaced:
/
14/9 8/5 / 5/3 12/7 / 16/9 / 15/8 48/25
5/4 9/7 / 4/3 / 7/5 10/7 / 3/2 /
1/1 / 25/24 16/15 / 9/8 / 7/6 6/5 /