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%I #7 Apr 19 2020 23:43:25
%S 0,5,72,1714,67100,4725018,611932378,148013550916,67580406047498,
%T 58605374440440754,97015414668307967168,307604236621005318739500,
%U 1873151902121241161650454526,21951627197224261891003815976598
%N Number of n X n binary arrays with some element plus some horizontally, vertically or antidiagonally adjacent neighbor totalling two exactly once.
%C Diagonal of A268789.
%H R. H. Hardin, <a href="/A268782/b268782.txt">Table of n, a(n) for n = 1..26</a>
%e Some solutions for n=4
%e ..0..1..0..0. .0..1..0..0. .0..0..0..1. .0..0..1..0. .0..0..1..0
%e ..0..0..0..1. .0..1..0..0. .1..0..0..0. .1..0..1..0. .0..0..0..1
%e ..1..1..0..0. .0..0..1..0. .0..0..1..0. .0..0..0..0. .0..1..0..0
%e ..0..0..0..0. .1..0..0..1. .1..0..1..0. .0..1..0..0. .0..0..1..1
%Y Cf. A268789.
%K nonn
%O 1,2
%A _R. H. Hardin_, Feb 13 2016
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