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 A331713 Number of nonnegative integer matrices with distinct nonzero rows, total sum n each column with the same sum and columns in nonincreasing lexicographic order. 2
 1, 3, 7, 18, 21, 147, 77, 1119, 2270, 12273, 1089, 464200, 4229, 4148223, 32941976, 159812905, 66153, 10211281004, 263321, 205923976532, 2439257062679, 3086915165084, 4199061, 1526043270802300, 311419986358517, 4817701809545446, 621665561741298232, 1898993198795136209 (list; graph; refs; listen; history; text; internal format)
 OFFSET 1,2 COMMENTS The condition that the columns be in nonincreasing order is equivalent to considering nonequivalent matrices up to permutation of columns. LINKS FORMULA a(n) = Sum_{d|n} A331572(n/d, d). EXAMPLE The a(2) = 3 matrices are:   [1 0]  [1 1]  [2]   [0 1] CROSSREFS Cf. A331572. Sequence in context: A222452 A218165 A102329 * A327321 A069143 A097007 Adjacent sequences:  A331710 A331711 A331712 * A331714 A331715 A331716 KEYWORD nonn AUTHOR Andrew Howroyd, Jan 25 2020 STATUS approved

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Last modified September 16 20:51 EDT 2021. Contains 347473 sequences. (Running on oeis4.)