666edo
666 EDO divides the octave into steps of 1.801 cents each.
Theory
Script error: No such module "primes_in_edo".
666edo is appropriate for use with the 2.11.19.41.43 subgroup, a choice with very large prime harmonics. If significant errors are allowed, 666edo can be used with 2.7.11.17.19.23. The alternations between approxmation make 666edo a good choice for "no-number" subgroups which skip particular harmonics.