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%I #4 Nov 02 2013 06:24:30
%S 0,144,13872,6170256,11094079744,66985909298064,1388708377137781120,
%T 101290675055736816040000,25961188014463809661357637024,
%U 23330456050837373777439681163833600
%N Number of (n+2)X(n+2) 0..3 arrays x(i,j) with each element diagonally or antidiagonally next to at least one element with value (x(i,j)+1) mod 4, no adjacent elements equal, and upper left element zero
%C Diagonal of A230977
%e Some solutions for n=2
%e ..0..2..0..2....0..3..0..3....0..1..0..1....0..1..0..3....0..3..0..1
%e ..1..1..3..3....2..1..0..3....2..1..2..3....2..1..0..3....0..1..2..1
%e ..2..0..0..2....0..1..2..3....2..3..0..1....2..3..0..3....0..1..2..1
%e ..3..3..1..3....0..3..0..1....2..3..0..3....2..3..2..3....0..3..0..1
%K nonn
%O 1,2
%A _R. H. Hardin_, Nov 02 2013