Search: id:A087982 Results 1-1 of 1 results found. %I A087982 %S A087982 1,0,2,8,24,128 %N A087982 Maximal permanent of a nonsingular n X n (+1,-1)-matrix. %C A087982 It is conjectured by Kraeuter and Seifter that for n >= 5 the maximal permanent of a nonsingular n X n (+1,-1)-matrix is attained by a matrix with exactly n-1 -1's on the diagonal (compare A087981). %C A087982 The maximal possible value for the permanent of a singular n X n (+1, -1)-matrix is obviously n!. %D A087982 A. R. Kraeuter and N. Seifter, Some properties of the permanent of (1, -1)-matrices, Linear and Multilinear Algebra 15 (1984), 207-223. %D A087982 N. Seifter, Upper bounds for permanents of (1,-1)-matrices, Israel J. Math. 48 (1984), 69-78. %D A087982 Edward Tzu-Hsia Wang, On permanents of (1,-1)-matrices, Israel J. Math. 18 (1974), 353-361. %H A087982 Index entries for sequences related to binary matrices %e A087982 a(4) = 8 from the following matrix: %e A087982 -1 +1 +1 +1 %e A087982 +1 +1 +1 +1 %e A087982 +1 -1 +1 -1 %e A087982 -1 +1 +1 -1 %Y A087982 The conjecture is that for n != 4 this is given by A087981. Cf. A087983. %Y A087982 Sequence in context: A157005 A123775 A052624 this_sequence A145238 A093458 A088994 %Y A087982 Adjacent sequences: A087979 A087980 A087981 this_sequence A087983 A087984 A087985 %K A087982 nonn %O A087982 1,3 %A A087982 N. J. A. Sloane (njas(AT)research.att.com), Oct 28 2003 %E A087982 a(4) = 8 from Edwin Clark and Wouter Meeussen, a(5) = 24 and a(6) = 128 from Jaap Spies, Oct 29 2003. Search completed in 0.001 seconds