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%I #7 Apr 19 2020 23:48:17
%S 0,108,46872,74853576,542973139128,19356924219624936,
%T 3516906597130333936872,3322606082327701612506093240,
%U 16524782213263820847479975782463640
%N Number of n X n 0..3 arrays with some element plus some horizontally or antidiagonally adjacent neighbor totalling three exactly once.
%C Diagonal of A269276.
%H R. H. Hardin, <a href="/A269269/b269269.txt">Table of n, a(n) for n = 1..11</a>
%e Some solutions for n=3
%e ..2..3..1. .0..2..3. .1..3..3. .2..0..0. .3..1..2. .3..3..1. .2..3..0
%e ..3..1..1. .3..3..3. .0..1..1. .2..2..1. .0..2..2. .2..3..2. .1..0..0
%e ..2..0..0. .2..0..1. .0..0..1. .3..1..0. .3..3..1. .1..1..0. .1..1..0
%Y Cf. A269276.
%K nonn
%O 1,2
%A _R. H. Hardin_, Feb 21 2016
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