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%I #6 Aug 20 2020 11:39:05
%S 0,1,3,36,1536,116954,27354464,16992197390,27071152148341,
%T 112124137590207769
%N Number of n X n 0..1 arrays with every element equal to 2, 3, 4 or 6 horizontally, vertically or antidiagonally adjacent elements, with upper left element zero.
%C Diagonal of A300776.
%e Some solutions for n=5
%e ..0..0..1..1..1. .0..0..0..1..1. .0..0..0..0..0. .0..0..0..0..0
%e ..0..0..1..1..0. .0..0..1..1..1. .0..1..1..1..0. .0..1..0..0..1
%e ..1..1..0..0..0. .1..1..0..0..1. .1..1..1..0..0. .1..1..0..1..1
%e ..1..1..0..1..1. .1..1..0..1..0. .1..1..0..1..1. .0..0..1..1..0
%e ..1..1..1..1..1. .1..1..1..0..0. .1..0..0..1..1. .0..1..1..0..0
%Y Cf. A300776.
%K nonn
%O 1,3
%A _R. H. Hardin_, Mar 12 2018