A206894 - OEIS

%I #6 Dec 18 2015 18:18:00

%S 4,256,211548,2408811358,369048436354154,768965608329861602588,

%T 21727183867324671091396681434

%N Number of n X n 0..3 arrays avoiding the pattern z-2 z-1 z in any row, column or nw-to-se diagonal

%C Diagonal of A206900

%e Some solutions for n=4

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

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

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

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

%K nonn

%O 1,1

%A _R. H. Hardin_ Feb 13 2012