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%I #4 Feb 21 2016 09:02:36
%S 0,27634932,23230366488,16128206816904,10181956012212600,
%T 6090616046325570480,3516906597130333936872,1980763969657041721006344,
%U 1095070756128723603201412440,596778595867621855341816843744
%N Number of 7Xn 0..3 arrays with some element plus some horizontally or antidiagonally adjacent neighbor totalling three exactly once.
%C Row 7 of A269276.
%H R. H. Hardin, <a href="/A269282/b269282.txt">Table of n, a(n) for n = 1..210</a>
%e Some solutions for n=2
%e ..0..0. .0..0. .0..0. .0..0. .0..0. .0..0. .0..0. .0..0. .0..0. .0..0
%e ..0..0. .0..0. .0..0. .0..0. .0..0. .0..0. .0..0. .0..0. .0..0. .0..0
%e ..0..1. .0..3. .0..1. .2..0. .0..2. .0..2. .2..1. .0..1. .2..2. .2..0
%e ..3..3. .1..0. .1..0. .3..2. .3..1. .3..0. .1..1. .3..1. .2..3. .1..0
%e ..0..1. .1..1. .1..0. .0..0. .0..1. .1..1. .1..0. .3..0. .2..3. .3..2
%e ..1..0. .3..1. .2..1. .0..1. .2..0. .1..0. .1..3. .2..2. .3..0. .2..0
%e ..1..3. .1..0. .3..1. .0..0. .0..1. .2..3. .1..3. .3..2. .2..2. .1..3
%Y Cf. A269276.
%K nonn
%O 1,2
%A _R. H. Hardin_, Feb 21 2016