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A330158
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Number of nonnegative integer matrices with total sum n, distinct columns with equal sums and any number of nonzero rows in nonincreasing lexicographic order.
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2
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1, 3, 4, 13, 8, 83, 16, 530, 630, 5620, 57, 119889, 102, 1901749, 1498322, 50091143, 298, 1649302673, 491, 54919254373, 16723808377, 2269075359300, 1256, 110133775311277, 26852941986, 5707320920415984, 622570195638208, 339574840900645411, 4566, 22572315004012650868
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OFFSET
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1,2
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COMMENTS
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The condition that the rows be in nonincreasing order is equivalent to considering nonequivalent matrices up to permutation of rows.
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LINKS
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FORMULA
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EXAMPLE
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The a(4) = 13 matrices are:
[1 0 0 0] [1 0] [1] [1 1] [2 0] [1 0] [2]
[0 1 0 0] [1 0] [1] [1 0] [0 1] [1 0] [1]
[0 0 1 0] [0 1] [1] [0 1] [0 1] [0 2] [1]
[0 0 0 1] [0 1] [1]
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[2 1] [2 0] [1 2] [3] [2] [4]
[0 1] [0 2] [1 0] [1] [2]
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CROSSREFS
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KEYWORD
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nonn
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AUTHOR
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STATUS
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approved
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