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%I #6 Oct 20 2020 19:27:31
%S 1,8,27,172,1581,23872,540901,26814986,2642187354,423954813814,
%T 137504464857165,84534178018042998,91922192531872367978
%N Number of n X n 0..1 arrays with every element unequal to 0, 1, 2, 3 or 7 king-move adjacent elements, with upper left element zero.
%C Diagonal of A304775.
%e Some solutions for n=5
%e ..0..0..1..0..0. .0..0..0..1..1. .0..0..0..0..1. .0..1..1..1..1
%e ..0..1..0..1..0. .0..0..1..0..0. .0..0..0..0..0. .1..1..1..0..1
%e ..0..0..0..0..0. .0..0..0..0..0. .0..1..0..0..0. .1..1..1..1..0
%e ..0..0..0..0..0. .0..0..1..0..0. .0..0..1..0..0. .0..1..1..1..0
%e ..1..0..0..0..1. .1..1..0..0..0. .1..0..0..0..0. .0..0..1..1..0
%Y Cf. A304775.
%K nonn
%O 1,2
%A _R. H. Hardin_, May 18 2018