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

0,7

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.

Sequence in context: A224046 A224277 A224200 * A224122 A223808 A223758

Adjacent sequences: A333897 A333898 A333899 * A333901 A333902 A333903

Keyword

nonn

Author

Andrew Howroyd, Apr 18 2020

Status

approved