A298049 - OEIS

%I #6 May 03 2020 15:42:12

%S 0,3,15,40,121,512,1708,7014,35804,201703,1158266,7391098,54852360

%N Number of n X n 0..1 arrays with every element equal to 1, 2, 4 or 6 king-move adjacent elements, with upper left element zero.

%C Diagonal of A298055.

%e Some solutions for n=5

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

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

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

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

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

%Y Cf. A298055.

%K nonn

%O 1,2

%A _R. H. Hardin_, Jan 11 2018