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%I #6 Sep 16 2020 18:58:28
%S 0,3,22,89,1307,20842,532511,17200486,683140749,61552556640
%N Number of n X n 0..1 arrays with every element equal to 1, 2, 4 or 6 horizontally, diagonally or antidiagonally adjacent elements, with upper left element zero.
%C Diagonal of A302728.
%e Some solutions for n=5
%e ..0..1..0..0..1. .0..0..1..1..1. .0..1..0..1..1. .0..1..1..1..0
%e ..0..0..1..1..0. .1..1..1..0..1. .1..0..0..0..1. .1..0..0..0..1
%e ..0..0..1..0..1. .1..0..0..0..1. .0..1..1..1..1. .1..1..1..1..1
%e ..1..1..1..0..1. .1..0..1..1..1. .1..1..1..1..0. .1..1..0..1..1
%e ..1..0..0..1..0. .1..1..1..0..0. .0..0..1..0..0. .0..0..1..0..0
%Y Cf. A302728.
%K nonn
%O 1,2
%A _R. H. Hardin_, Apr 12 2018