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%I #7 Apr 19 2020 23:46:30
%S 3,42,594,24192,1643376,242861616,71430596250,43961616939276,
%T 56121206116838532,149312689805356303800,836315757545942679945480,
%U 9777884421682321788379713444,242268002268280142077867206348378
%N Number of n X n 0..2 arrays with some element plus some horizontally, diagonally or antidiagonally adjacent neighbor totalling two not more than once.
%C Diagonal of A269052.
%H R. H. Hardin, <a href="/A269046/b269046.txt">Table of n, a(n) for n = 1..14</a>
%e Some solutions for n=4
%e ..2..0..1..2. .1..2..1..2. .0..2..1..0. .2..2..2..2. .0..2..1..2
%e ..1..2..1..0. .1..2..1..0. .1..0..1..0. .1..1..2..2. .1..0..1..2
%e ..1..2..1..0. .1..0..1..0. .0..0..0..0. .2..2..2..1. .0..0..1..0
%e ..1..0..1..0. .1..2..0..0. .0..0..0..1. .1..2..2..2. .0..0..1..0
%Y Cf. A269052.
%K nonn
%O 1,1
%A _R. H. Hardin_, Feb 18 2016
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