A231102 - OEIS

%I #5 Dec 18 2015 18:18:45

%S 0,0,8,438,75346,48463174,110728004898,879549454424322,

%T 24425156030389837162,2380336656518678938694450,

%U 814656324267500393611361701060

%N Number of n X n 0..3 arrays x(i,j) with each element horizontally 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 A231108

%e Some solutions for n=4

%e ..0..1..2..3....0..1..0..1....0..1..2..1....0..1..2..1....0..1..2..0

%e ..0..1..0..3....2..3..2..3....0..3..2..3....2..3..0..2....0..3..1..2

%e ..2..3..0..3....0..1..0..1....0..1..0..3....1..2..3..2....1..2..3..2

%e ..2..1..0..3....2..3..2..1....0..1..2..1....1..0..1..0....1..0..3..2

%K nonn

%O 1,3

%A _R. H. Hardin_, Nov 03 2013