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%I #4 Mar 31 2012 12:36:08
%S 36,4332,2164680,4935992256,54448184779776,3028538328016591872
%N Number of (n+1)X(n+1) 0..5 arrays with diagonal zero and the i,j-th 2X2 subblock sum equal to the j,i-th 2X2 subblock sum
%C Column 5 of A187408
%e Some solutions for 4X4
%e ..0..3..0..3....0..3..3..1....0..3..3..3....0..3..3..3....0..0..0..3
%e ..1..0..2..4....3..0..0..2....2..0..4..1....5..0..4..1....0..0..4..1
%e ..0..4..0..4....2..1..0..1....4..4..0..3....1..4..0..5....2..2..0..0
%e ..4..1..5..0....2..1..1..0....1..2..2..0....3..3..3..0....3..1..2..0
%K nonn
%O 1,1
%A _R. H. Hardin_ Mar 09 2011