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%I #6 Sep 16 2020 19:15:38
%S 1,8,41,322,5063,89071,1802240,101407827,8813328376,823379005870
%N Number of n X n 0..1 arrays with every element unequal to 0, 1, 2, 3 or 6 king-move adjacent elements, with upper left element zero.
%C Diagonal of A304472.
%e Some solutions for n=5
%e ..0..0..0..0..0. .0..1..1..1..1. .0..0..1..1..0. .0..1..1..1..1
%e ..0..0..0..0..0. .0..1..1..1..1. .0..1..1..0..0. .0..0..1..1..1
%e ..0..0..0..1..0. .0..1..1..1..1. .1..1..1..1..1. .1..1..1..1..1
%e ..0..0..0..1..1. .0..1..1..1..1. .1..1..0..1..1. .1..1..1..0..0
%e ..1..0..0..0..0. .0..1..1..1..0. .0..1..0..0..1. .1..1..1..1..0
%Y Cf. A304472.
%K nonn
%O 1,2
%A _R. H. Hardin_, May 13 2018