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%I #6 Apr 20 2020 19:51:23
%S 4,180,25572,15289548,34838403756,320994710282892,
%T 12093315071771856492,1887658657444603460395332,
%U 1230222115345954315761363474780,3366670969596963372379333414861881876
%N Number of n X n 0..3 arrays with some element plus some horizontally, diagonally or antidiagonally adjacent neighbor totalling three no more than once.
%C Diagonal of A269201.
%e Some solutions for n=3
%e ..0..2..0. .0..1..0. .3..1..3. .0..0..1. .1..0..0. .3..1..2. .0..0..0
%e ..0..1..3. .1..1..1. .0..3..3. .0..0..1. .1..0..1. .3..2..0. .2..0..0
%e ..0..1..3. .3..1..3. .3..1..1. .0..1..0. .3..3..1. .2..2..0. .2..0..1
%Y Cf. A269201.
%K nonn
%O 1,1
%A _R. H. Hardin_, Feb 20 2016
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