A206951 - OEIS

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

%S 3,81,11804,9803278,50967712088,1627105474024831,

%T 314368117565737962789,368862218847158027158758198

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

%C Diagonal of A206957

%e Some solutions for n=4

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

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

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

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

%K nonn

%O 1,1

%A _R. H. Hardin_ Feb 13 2012