A299009 - OEIS

%I #6 Jun 15 2020 14:06:44

%S 1,7,20,174,6908,379236,59666756,22388413097,20692923925827

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

%C Diagonal of A299015.

%e Some solutions for n=5

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

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

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

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

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

%Y Cf. A299015.

%K nonn

%O 1,2

%A _R. H. Hardin_, Jan 31 2018