%I #5 Dec 18 2015 18:17:27
%S 1,3,67,21350,147512732,30761087800216
%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 diagonal or antidiagonal neighbor
%e Some solutions for n=4
%e ..0........0........0........0........0........0........0........0
%e ..1.2......1.2......1.1......1.2......1.2......1.2......0.1......0.1
%e ..1.2.1....3.3.4....2.3.4....0.3.0....0.3.3....3.2.3....0.2.2....2.3.4
%e ..3.2.4.0..4.5.1.2..5.3.6.0..2.1.1.3..4.5.6.7..3.1.4.0..0.3.0.1..2.5.0.6
%K nonn
%O 1,2
%A _R. H. Hardin_ Apr 26 2012
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