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A331645 Number of nonnegative integer matrices with n columns and any number of distinct nonzero rows with column sums 3. 5
1, 3, 87, 11655, 4498191, 3611504823, 5192498314767, 12172382140406295, 43436006002867938351, 224018914608150321575223, 1603777845822934662938327247, 15430102163147097295950086754135, 194280602846166109497542618768659311, 3131120528310366432743101620841328437623 (list; graph; refs; listen; history; text; internal format)
OFFSET

0,2

LINKS

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

EXAMPLE

The a(1) = 3 matrices are:

   [2]  [1]  [3]

   [1]  [2]

CROSSREFS

Row n=3 of A331568.

Cf. A331644.

Sequence in context: A230670 A232069 A172723 * A037112 A093748 A156737

Adjacent sequences:  A331642 A331643 A331644 * A331646 A331647 A331648

KEYWORD

nonn

AUTHOR

Andrew Howroyd, Jan 23 2020

STATUS

approved

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Last modified December 9 09:37 EST 2021. Contains 349627 sequences. (Running on oeis4.)