A221976 The number of n X n matrices with zero determinant and with entries a permutation of [1,2,..,n^2].
0, 0, 2736, 8290316160
Offset: 1
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a(40800)=1 because the only 4X4 matrices with elements 1...16 with the determinant 40800 are the 576 combinations of determinant-preserving row and column permutations of ((16 6 4 9)(8 13 11 1)(3 12 5 14)(7 2 15 10)).
a(4)=16: There are 2*a(4) = 32 4 X 4 Latin squares with determinant = 0, one of which is [1 4 3 2] [4 1 2 3] [3 2 1 4] [2 3 4 1]. An example of a 6 X 6 Latin square with determinant = 0 is [1 3 4 6 5 2] [3 2 6 5 4 1] [4 6 3 2 1 5] [6 5 1 3 2 4] [5 4 2 1 3 6] [2 1 5 4 6 3].
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