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%I #5 Dec 18 2015 18:17:46
%S 1,1,9,369,68551,65530899,314737269521
%N Number of lower triangles of an n X n integer array with all row and column sums zero and all row and column sums of squares <=32
%C Column 4 of A195892
%e Some solutions for n=4
%e ..0........0........0........0........0........0........0........0
%e ..3-3.....-4.4.....-2.2......4-4......4-4.....-3.3.....-2.2......2-2
%e ..1.3-4....2-3.1....2-1-1...-3.4-1....0.0.0....0.1-1....2.1-3...-4.4.0
%e .-4.0.4.0..2-1-1.0..0-1.1.0.-1.0.1.0.-4.4.0.0..3-4.1.0..0-3.3.0..2-2.0.0
%K nonn
%O 1,3
%A _R. H. Hardin_ Sep 24 2011
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