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%I #12 Dec 18 2015 18:17:27
%S 1,2,35,8292,43324498,7006657352045
%N Number of lower triangular n X n arrays colored with integers 0 upwards introduced in row major order, with no element equal to any horizontal, diagonal or antidiagonal neighbor
%e Some solutions for n=4
%e ..0........0........0........0........0........0........0........0
%e ..0.1......1.2......1.2......1.2......1.2......1.2......1.2......0.1
%e ..2.3.4....1.0.3....3.4.1....0.3.4....3.4.5....1.3.0....3.4.1....2.1.3
%e ..1.3.4.2..1.4.1.4..2.4.5.3..1.3.1.2..5.4.5.2..4.3.1.2..5.0.1.5..0.1.2.0
%K nonn
%O 1,2
%A _R. H. Hardin_ Apr 26 2012
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