%I #6 Jun 15 2020 13:57:10
%S 0,3,15,40,123,516,1818,7768,41048,242083,1483959,10171555
%N Number of n X n 0..1 arrays with every element equal to 1, 2, 4, 6 or 8 king-move adjacent elements, with upper left element zero.
%C Diagonal of A298888.
%e Some solutions for n=7
%e ..0..1..0..1..0..0..0. .0..1..1..0..0..1..1. .0..0..1..0..0..1..1
%e ..1..0..0..1..1..1..1. .1..0..0..0..0..0..0. .1..0..1..1..1..0..0
%e ..0..0..0..1..1..1..0. .1..0..0..0..1..0..1. .0..1..0..1..0..1..0
%e ..0..0..1..1..1..1..0. .0..0..0..0..1..1..0. .0..1..1..1..1..1..1
%e ..0..1..0..1..1..1..1. .0..0..1..1..0..1..0. .1..0..1..1..1..0..0
%e ..0..0..1..1..0..0..0. .1..0..0..1..1..0..1. .1..0..1..1..1..0..1
%e ..1..1..0..0..1..1..1. .1..0..1..0..0..1..0. .1..0..1..0..0..1..0
%Y Cf. A298888.
%K nonn
%O 1,2
%A _R. H. Hardin_, Jan 28 2018
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