A196315 - OEIS

%I #6 Dec 18 2015 18:17:47

%S 1,7,30,495,17093,1313940,228181579,88027683663,75477277195192,

%T 143743832507166333

%N Number of n X n 0..4 arrays with each element x equal to the number of its horizontal and vertical neighbors equal to 1,3,0,2,4 for x=0,1,2,3,4

%C Every 0 is next to 0 1's, every 1 is next to 1 3's, every 2 is next to 2 0's, every 3 is next to 3 2's, every 4 is next to 4 4's

%C Diagonal of A196322

%e Some solutions for n=4

%e ..0..2..0..0....0..2..0..0....0..0..0..2....0..2..0..0....2..0..2..0

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

%e ..0..0..0..0....0..0..0..0....2..2..2..0....0..0..2..2....0..2..0..0

%e ..0..0..0..0....0..2..2..0....0..0..2..0....2..0..2..0....0..2..0..2

%K nonn

%O 1,2

%A _R. H. Hardin_ Oct 01 2011