%I #6 Sep 16 2020 19:07:56
%S 1,4,17,90,562,5282,15478,394667,587035,47608207,23125171,8706714125,
%T 1066431672,2470846969189,56568350211,1133933765289063,3650604967363
%N Number of n X n 0..1 arrays with every element unequal to 0, 1, 2 or 4 king-move adjacent elements, with upper left element zero.
%C Diagonal of A303800.
%e Some solutions for n=5
%e ..0..1..1..0..0. .0..1..0..1..0. .0..1..0..0..1. .0..1..1..1..1
%e ..0..1..1..0..0. .1..0..0..0..1. .1..0..0..0..1. .0..1..1..1..1
%e ..1..1..1..1..0. .0..0..0..0..0. .0..0..0..0..0. .1..1..1..1..1
%e ..1..1..1..1..0. .1..0..0..0..1. .0..0..0..0..1. .1..1..1..1..1
%e ..0..0..1..1..1. .1..0..0..1..0. .1..1..0..0..1. .1..1..0..0..1
%Y Cf. A303800.
%K nonn
%O 1,2
%A _R. H. Hardin_, Apr 30 2018
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