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A331707
Number of nonnegative integer matrices with 3 distinct columns and any number of distinct nonzero rows with column sums n and columns in decreasing lexicographic order.
2
0, 1, 46, 1900, 73028, 2448599, 75497242, 2339274204, 69674762468, 1979828352817, 54476556180342, 1451352388018928, 37417987990316376, 936855054326483475, 22833066202591181758, 542259452432969505704, 12569324678536063256324, 284784345516356806067001, 6313245421002223574950650
OFFSET
0,3
COMMENTS
The condition that the columns be in decreasing order is equivalent to considering nonequivalent matrices with distinct columns up to permutation of columns.
EXAMPLE
The a(1) = 1 matrix is:
[1 0 0]
[0 1 0]
[0 0 1]
CROSSREFS
Column k=3 of A331570.
Cf. A331706.
Sequence in context: A318044 A263190 A364119 * A223813 A324451 A162889
KEYWORD
nonn
AUTHOR
Andrew Howroyd, Jan 25 2020
STATUS
approved