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%I #4 Nov 20 2017 11:33:57
%S 1,13,10,33,84,338,84,360,1200,10020,42976,10020,12003600,42795,
%T 145485,1206772,4848581,21059938,4848585,1206796,145473,42807,3600
%N a(n) = number of (0,1) matrices of size n X n whose determinants are k, where -L <= k <= +L and L = A003432(n).
%H J. Brenner, <a href="http://www.jstor.org/stable/2317092">The Hadamard maximum determinant problem</a>, Amer. Math. Monthly, 79 (1972), 626-630.
%H J. Williamson, <a href="http://www.jstor.org/stable/2306240">Determinants whose elements are 0 and 1</a>, Amer. Math. Monthly 53 (1946), 427-434. Math. Rev. 8,128g.
%e n = 2 : det([a b];[c d]) is (ad - bc) [16 possible matrices]
%e 0 if ((a OR d) = zero) AND ((b OR c) = zero)
%e OR ((a AND d) = one) AND ((b AND D) = one) [10 possible matrices]
%e +1 if ((a AND d) = one) AND ((b OR c) = zero) [ 3 possible matrices]
%e -1 if ((a OR d) = zero) AND ((b AND c) = one) [ 3 possible matrices]
%Y Cf. A003432, A003433.
%K hard,nonn
%O 1,2
%A Patricia J. Egan (capdevcom(AT)lycos.com), Jun 11 2004
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