|
%I #5 Dec 18 2015 18:17:41
%S 0,1,17,525,60155,26946822,36060642759,159137536303316,
%T 2292846876178991797
%N Number of n X n symmetric 0..3 arrays with each element equal to the sum mod 4 of two of its horizontal and vertical neighbors
%e Some solutions for 4X4
%e ..0..0..2..0....0..2..2..0....2..1..1..0....0..2..1..0....0..2..2..3
%e ..0..0..2..2....2..1..3..2....1..3..2..3....2..2..1..3....2..1..3..1
%e ..2..2..3..1....2..3..0..2....1..2..0..1....1..1..2..2....2..3..2..2
%e ..0..2..1..2....0..2..2..0....0..3..1..2....0..3..2..0....3..1..2..0
%K nonn
%O 1,3
%A _R. H. Hardin_ Jul 16 2011
| 