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A333902 Number of nonequivalent 3 X n nonnegative integer matrices with all column sums 3 and row sums n up to permutation of rows. 2
1, 1, 2, 10, 70, 566, 4781, 41357, 364470, 3257830, 29450557, 268701797, 2470513849, 22862694505, 212758007450, 1989477010250, 18682005254390, 176085344355510, 1665167298000005, 15793406377949405, 150192477267201945, 1431741484334863145, 13678227386467491410 (list; graph; refs; listen; history; text; internal format)
OFFSET
0,3
COMMENTS
Number of factorizations of m^3 into 3 factors, where m is a product of exactly n distinct primes and each factor is a product of n primes (counted with multiplicity).
LINKS
EXAMPLE
The a(2) = 2 matrices are:
[1 1] [0 2]
[1 1] [1 1]
[1 1] [2 0]
CROSSREFS
Row n=3 of A257462.
Sequence in context: A166076 A354307 A217938 * A051405 A005568 A036075
KEYWORD
nonn
AUTHOR
Andrew Howroyd, Apr 18 2020
STATUS
approved

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Last modified February 21 03:13 EST 2024. Contains 370219 sequences. (Running on oeis4.)