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%I #6 Feb 20 2016 06:50:05
%S 60,1164,18556,275796,3924212,54199284,732561916,9740150372,
%T 127846717716,1660741102212,21389485726684,273519303765844,
%U 3476418550368820,43954347343683220,553215363420258236,6935081471870462788
%N Number of nX3 0..3 arrays with some element plus some horizontally, antidiagonally or vertically adjacent neighbor totalling three no more than once.
%C Column 3 of A269143.
%H R. H. Hardin, <a href="/A269138/b269138.txt">Table of n, a(n) for n = 1..210</a>
%F Empirical: a(n) = 26*a(n-1) -199*a(n-2) +408*a(n-3) -463*a(n-4) +322*a(n-5) -141*a(n-6) +36*a(n-7) -4*a(n-8) for n>9
%e Some solutions for n=3
%e ..3..2..2. .1..0..0. .0..0..2. .1..1..1. .3..1..0. .1..1..3. .1..3..1
%e ..3..2..2. .2..0..2. .1..3..3. .0..3..1. .3..0..2. .3..3..3. .1..1..3
%e ..3..3..2. .0..2..0. .3..1..1. .1..1..3. .2..0..0. .2..2..2. .1..0..1
%Y Cf. A269143.
%K nonn
%O 1,1
%A _R. H. Hardin_, Feb 20 2016
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