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A094813 a(n) = number of (0,1) matrices of size n X n whose determinants are k, where -L <= k <= +L and L = A003432(n). 0
1, 13, 10, 33, 84, 338, 84, 360, 1200, 10020, 42976, 10020, 12003600, 42795, 145485, 1206772, 4848581, 21059938, 4848585, 1206796, 145473, 42807, 3600 (list; graph; refs; listen; history; internal format)
OFFSET

1,2

REFERENCES

J. Brenner, The Hadamard maximum determinant problem, Amer. Math. Monthly, 79 (1972), 626-630

J. Williamson, Determinants whose elements are 0 and 1, Amer. Math. Monthly 53 (1946), 427-434. Math. Rec. 8,128g

EXAMPLE

n = 2 : det([a b];[c d]) is (ad - bc) [16 possible matrices]

0 if ((a OR d) = zero) AND ((b OR c) = zero)

OR ((a AND d) = one) AND ((b AND D) = one) [10 possible matrices]

+1 if ((a AND d) = one) AND ((b OR c) = zero) [ 3 possible matrices]

-1 if ((a OR d) = zero) AND ((b AND c) = one) [ 3 possible matrices]

CROSSREFS

Cf. A003432, A003433.

Sequence in context: A072270 A180864 A206608 * A152298 A158956 A160130

Adjacent sequences:  A094810 A094811 A094812 * A094814 A094815 A094816

KEYWORD

hard,nonn

AUTHOR

Patricia J. Egan (capdevcom(AT)lycos.com), Jun 11 2004

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Last modified February 14 06:42 EST 2012. Contains 205574 sequences.