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%I #4 Feb 20 2016 11:34:29
%S 0,7375872,2039727744,599456856000,163535201141376,43468685827935816,
%T 11273191243423937904,2872961996154823592256,722010748558146090563664,
%U 179436639887553691981747008,44187481124719769649267286128
%N Number of 7Xn 0..3 arrays with some element plus some horizontally, diagonally or antidiagonally adjacent neighbor totalling three exactly once.
%C Row 7 of A269214.
%H R. H. Hardin, <a href="/A269220/b269220.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..2. .0..0. .0..0. .0..0. .0..0. .0..2. .0..0. .0..0. .0..2. .0..0
%e ..2..0. .0..1. .1..0. .1..0. .0..0. .0..2. .1..1. .1..1. .0..0. .1..3
%e ..2..3. .3..3. .1..1. .2..3. .2..2. .2..2. .2..3. .0..1. .0..0. .3..1
%e ..1..1. .2..2. .1..3. .0..2. .3..3. .3..2. .2..2. .3..2. .1..3. .3..1
%e ..3..1. .2..3. .3..2. .3..2. .2..1. .0..3. .2..0. .1..3. .1..1. .3..2
%e ..3..2. .3..3. .3..2. .3..3. .0..0. .2..2. .1..3. .1..3. .0..0. .0..1
%Y Cf. A269214.
%K nonn
%O 1,2
%A _R. H. Hardin_, Feb 20 2016