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A269189 Number of nX3 0..3 arrays with some element plus some horizontally, diagonally, antidiagonally or vertically adjacent neighbor totalling three no more than once. 1

%I

%S 60,708,9284,115452,1399612,16629436,194596516,2249848972,25758552060,

%T 292530733516,3299601105860,37002081127036,412867979588732,

%U 4586651556698652,50758470773069860,559808285415404076

%N Number of nX3 0..3 arrays with some element plus some horizontally, diagonally, antidiagonally or vertically adjacent neighbor totalling three no more than once.

%C Column 3 of A269194.

%H R. H. Hardin, <a href="/A269189/b269189.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 ..0..0..1. .0..2..3. .1..0..0. .1..1..3. .1..1..3. .3..1..1. .0..0..1

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

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

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

%Y Cf. A269194.

%K nonn

%O 1,1

%A _R. H. Hardin_, Feb 20 2016

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Last modified December 2 13:56 EST 2021. Contains 349445 sequences. (Running on oeis4.)