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 A309984 Number of n X n Latin squares with determinant 0, divided by 2. 3
 0, 0, 0, 16, 0, 2088, 5752, 199600889 (list; graph; refs; listen; history; text; internal format)
 OFFSET 1,4 LINKS Brendan McKay, Latin squares. Hugo Pfoertner, Occurrence counts of determinant values of Latin squares for n=1..8, zipped (2019). EXAMPLE 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]. CROSSREFS Cf. A040082, A136609, A221976, A301371, A308853, A309258, A309985. Sequence in context: A221380 A221759 A111979 * A173436 A081263 A265491 Adjacent sequences:  A309981 A309982 A309983 * A309985 A309986 A309987 KEYWORD nonn,more,hard AUTHOR Hugo Pfoertner, Aug 26 2019 STATUS approved

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Last modified December 10 00:54 EST 2019. Contains 329885 sequences. (Running on oeis4.)