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A269181 Number of nX3 0..3 arrays with some element plus some horizontally, diagonally, antidiagonally or vertically adjacent neighbor totalling three exactly once. 1

%I

%S 24,384,5888,80112,1031344,12791896,154606864,1833130768,21416076480,

%T 247279304248,2828051682752,32088228414160,361662427633424,

%U 4053056289550296,45198059875209904,501865175240768976

%N Number of nX3 0..3 arrays with some element plus some horizontally, diagonally, antidiagonally or vertically adjacent neighbor totalling three exactly once.

%C Column 3 of A269186.

%H R. H. Hardin, <a href="/A269181/b269181.txt">Table of n, a(n) for n = 1..210</a>

%F Empirical: a(n) = 22*a(n-1) -131*a(n-2) +88*a(n-3) +221*a(n-4) -154*a(n-5) -101*a(n-6) +44*a(n-7) -4*a(n-8) for n>9

%e Some solutions for n=4

%e ..1..2..0. .0..0..0. .3..1..2. .1..1..0. .1..0..1. .3..0..1. .3..1..2

%e ..0..0..2. .2..0..2. .3..3..3. .3..3..1. .0..1..0. .1..1..0. .1..3..3

%e ..2..0..0. .2..2..2. .1..1..1. .2..3..1. .1..0..2. .1..1..1. .3..3..2

%e ..2..2..2. .3..0..2. .1..1..0. .3..3..1. .1..0..0. .1..0..0. .2..2..3

%Y Cf. A269186.

%K nonn

%O 1,1

%A _R. H. Hardin_, Feb 20 2016

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Last modified August 20 18:56 EDT 2019. Contains 326154 sequences. (Running on oeis4.)