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%I #13 Aug 29 2019 20:16:11
%S 0,0,0,16,0,2088,5752,199600889
%N Number of n X n Latin squares with determinant 0, divided by 2.
%H Brendan McKay, <a href="https://users.cecs.anu.edu.au/~bdm/data/latin.html">Latin squares</a>.
%H Hugo Pfoertner, <a href="http://www.randomwalk.de/sequences/a309258.zip">Occurrence counts of determinant values of Latin squares for n=1..8</a>, zipped (2019).
%e a(4)=16: There are 2*a(4) = 32 4 X 4 Latin squares with determinant = 0, one of which is
%e [1 4 3 2]
%e [4 1 2 3]
%e [3 2 1 4]
%e [2 3 4 1].
%e An example of a 6 X 6 Latin square with determinant = 0 is
%e [1 3 4 6 5 2]
%e [3 2 6 5 4 1]
%e [4 6 3 2 1 5]
%e [6 5 1 3 2 4]
%e [5 4 2 1 3 6]
%e [2 1 5 4 6 3].
%Y Cf. A040082, A136609, A221976, A301371, A308853, A309258, A309985.
%K nonn,more,hard
%O 1,4
%A _Hugo Pfoertner_, Aug 26 2019
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