A333900 Number of nonequivalent n X n binary matrices with 4 ones in every row and column up to permutation of rows.

1, 0, 0, 0, 1, 1, 130, 16700, 3330915, 957659906, 382304435016, 204772106834160, 143299238797934175, 128179127293763395905, 143868740984351881041401, 199438057945979365292917046, 336793287548313747690192184440, 684521312346990661869780271166300

Offset: 0

Author

Andrew Howroyd, Apr 18 2020

Keywords

• nonn

Comments

Number of factorizations of m^4 into n factors, where m is a product of exactly n distinct primes and each factor is a product of 4 distinct primes.

Links

• Andrew Howroyd, Table of n, a(n) for n = 0..50

Crossrefs

Column k=4 of A260340.

Cf. A268668.