A297987 - OEIS

%I #6 May 03 2020 15:41:55

%S 0,4,48,466,5100,74675,1276012,30240388,1056360518,50037661325,

%T 3406737828874,353272517327686,52791942245108114

%N Number of n X n 0..1 arrays with every element equal to 1, 2, 3 or 6 king-move adjacent elements, with upper left element zero.

%C Diagonal of A297993.

%e Some solutions for n=6

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

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

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

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

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

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

%Y Cf. A297993.

%K nonn

%O 1,2

%A _R. H. Hardin_, Jan 10 2018