A222491 - OEIS

%I #3 Feb 22 2013 08:04:04

%S 0,13,85,270,2373,17095,145019,1271237,12273588,113823904,1131311866,

%T 10543094777,105359579523,985710462356,9862145116373,92538102045091,

%U 925649183459093

%N Number of 4Xn 0..2 arrays with exactly floor(4Xn/2) elements unequal to at least one horizontal, diagonal or antidiagonal neighbor, with new values introduced in row major 0..2 order

%C Row 4 of A222488

%e Some solutions for n=4

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

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

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

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

%K nonn

%O 1,2

%A _R. H. Hardin_ Feb 22 2013