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A088672
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Number of n X n (0,1)-matrices with zero permanent.
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9
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OFFSET
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0,3
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LINKS
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FORMULA
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a(n) is asymptotic to n*(2^(n^2 - n + 1)). [Everett and Stein]
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MATHEMATICA
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a[ n_] := Count[Table[Permanent[Partition[a, n]], {a, Tuples[{0, 1}, n^2]}], 0]; (* Michael Somos, Aug 05 2018 *)
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CROSSREFS
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KEYWORD
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nonn,more,hard
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AUTHOR
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EXTENSIONS
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STATUS
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approved
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