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A333899 Number of nonequivalent n X n binary matrices with 3 ones in every row and column up to permutation of rows. 2
1, 0, 0, 1, 1, 22, 550, 16700, 703297, 38135272, 2584332084, 214050246975, 21269928579625, 2497135296996934, 341930210261762434, 54008226638062039798, 9746833030828647070625, 1993080976749664740373600, 458405276998431265342151848, 117814680468332544208002721773 (list; graph; refs; listen; history; text; internal format)
OFFSET

0,6

COMMENTS

Number of factorizations of m^3 into n factors, where m is a product of exactly n distinct primes and each factor is a product of 3 distinct primes.

LINKS

Andrew Howroyd, Table of n, a(n) for n = 0..100

CROSSREFS

Column k=3 of A260340.

Cf. A254243.

Sequence in context: A320766 A203456 A271266 * A239652 A223883 A223890

Adjacent sequences:  A333896 A333897 A333898 * A333900 A333901 A333902

KEYWORD

nonn

AUTHOR

Andrew Howroyd, Apr 18 2020

STATUS

approved

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Last modified October 15 21:38 EDT 2021. Contains 348034 sequences. (Running on oeis4.)