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%I #4 Mar 31 2012 12:35:50
%S 2,5,75,29721,331189203
%N Number of nXnXnXn triangular pyramidal binary arrays with the number of 0-0 adjacencies equal to the number of 0-1 adjacencies
%e Some solutions for 3X3X3X3
%e ....0......1......0......0......0......1......0......0......1......0......1
%e ...
%e ....0......1......0......0......1......0......0......1......0......0......0
%e ...0.1....0.0....0.0....0.1....0.0....0.0....0.0....0.0....0.1....0.0....0.0
%e ...
%e ....1......0......1......0......0......1......1......0......0......1......0
%e ...0.1....0.1....1.0....0.0....0.0....0.0....0.0....0.0....0.0....1.1....1.0
%e ..0.0.0..0.0.0..1.0.1..1.1.0..0.1.0..1.0.1..1.1.1..1.0.1..0.1.0..0.0.1..0.0.1
%K nonn
%O 1,1
%A _R. H. Hardin_ Jan 03 2011