11 herculean symbol pairs

These are 11 pairs of symbols which allow one to express any interval
of hercules in the form 2^a * (3/2)^b * symbol. Obviously, we could
use more symbols if we wanted, but this pair of 11 symbols will do
the job efficiently, even without an 81/80 (for instance.) Below I
give the interval which defines the symbol pair, and its expression
in hercules using the 81/80-64/63 basis. Possibly a 35/32-64/63 basis
or a 10/9-64/63 basis would be better, using symbols from the set,
though that gets us away from the flags.

64/63 [0, 1]
35/32 [1, 5]
10/9 [1, 6]
44/39 [1, 7]
55/48 [1, 8]
100/81 [2, 12]
351/280 [2, 13]
14/11 [2, 14]
39/28 [3, 19]
99/70 [3, 20]
65/42 [4, 25]