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%I #5 Dec 18 2015 18:17:42
%S 1,2,42,12422,46043957,1141280241767,150904343382960765,
%T 103330870123503516426952,365608923633974657544208900050,
%U 6683711936086156432904840085269243480
%N Number of n X n symmetric 0..6 arrays with no element equal to any horizontal or vertical neighbor and with new values 0..6 introduced in lower triangular row major order
%e Some solutions for 4X4
%e ..0..1..3..2....0..1..3..5....0..1..2..4....0..1..3..0....0..1..3..1
%e ..1..2..4..0....1..2..0..6....1..2..3..0....1..2..4..5....1..2..4..5
%e ..3..4..5..2....3..0..4..2....2..3..1..2....3..4..0..2....3..4..0..6
%e ..2..0..2..3....5..6..2..3....4..0..2..1....0..5..2..4....1..5..6..3
%K nonn
%O 1,2
%A _R. H. Hardin_ Jul 20 2011