A304698 - OEIS

%I #6 Oct 20 2020 19:26:52

%S 0,3,8,48,908,47440,3510334,799135415,758781064050

%N Number of n X n 0..1 arrays with every element unequal to 1, 2, 4, 5 or 6 king-move adjacent elements, with upper left element zero.

%C Diagonal of A304704.

%e Some solutions for n=5

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

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

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

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

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

%Y Cf. A304704.

%K nonn

%O 1,2

%A _R. H. Hardin_, May 17 2018