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A333900
Number of nonequivalent n X n binary matrices with 4 ones in every row and column up to permutation of rows.
3
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
CROSSREFS
Column k=4 of A260340.
Cf. A268668.
Sequence in context: A224046 A224277 A224200 * A224122 A223808 A223758
KEYWORD
nonn
AUTHOR
Andrew Howroyd, Apr 18 2020
STATUS
approved