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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 (list; graph; refs; listen; history; text; internal format)
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

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Last modified December 6 13:24 EST 2021. Contains 349563 sequences. (Running on oeis4.)