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A000410
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Number of singular n X n rational (0,1)-matrices.
(Formerly M4308 N1803)
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10
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OFFSET
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1,3
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COMMENTS
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Number of all n X n (0,1)-matrices having distinct, nonzero ordered rows and determinant 0 - compare A000409.
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REFERENCES
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N. J. A. Sloane, A Handbook of Integer Sequences, Academic Press, 1973 (includes this sequence).
N. J. A. Sloane and Simon Plouffe, The Encyclopedia of Integer Sequences, Academic Press, 1995 (includes this sequence).
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LINKS
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FORMULA
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n! * a(n) = A046747(n) - 2^(n^2) + n! * binomial(2^n -1, n).
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CROSSREFS
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KEYWORD
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nonn,nice,more
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AUTHOR
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EXTENSIONS
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n=7 term from Guenter M. Ziegler (ziegler(AT)math.TU-Berlin.DE)
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STATUS
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approved
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