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%I #7 Apr 19 2020 23:42:38
%S 0,6,56,1148,32056,1552272,127676872,18045771274,4495138018796,
%T 1955829240647962,1511334747222697904,2064152526111916503300,
%U 5022957354228609008158500,21748481726801956896608976098
%N Number of n X n binary arrays with some element plus some horizontally, vertically, diagonally or antidiagonally adjacent neighbor totalling two exactly once.
%C Diagonal of A268766.
%H R. H. Hardin, <a href="/A268760/b268760.txt">Table of n, a(n) for n = 1..26</a>
%e Some solutions for n=4
%e ..0..0..1..1. .0..0..0..0. .0..1..0..1. .0..0..0..1. .0..0..0..0
%e ..1..0..0..0. .1..0..0..0. .0..0..0..0. .1..1..0..0. .1..0..0..1
%e ..0..0..0..1. .0..0..0..1. .1..0..0..0. .0..0..0..1. .1..0..0..0
%e ..1..0..0..0. .0..1..0..1. .1..0..1..0. .0..1..0..0. .0..0..0..1
%Y Cf. A268766.
%K nonn
%O 1,2
%A _R. H. Hardin_, Feb 13 2016
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