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 A277940 Number of nX3 0..2 arrays with every element plus 1 mod 3 equal to some element at offset (-1,0) (-1,1) (0,-1) (0,1) or (1,0), with upper left element zero. 1

%I

%S 0,14,172,2353,31011,410047,5417792,71585918,945856876,12497509310,

%T 165128212197,2181820850641,28828157762271,380903262040913,

%U 5032832696491638,66498262088947407,878634186243031144

%N Number of nX3 0..2 arrays with every element plus 1 mod 3 equal to some element at offset (-1,0) (-1,1) (0,-1) (0,1) or (1,0), with upper left element zero.

%C Column 3 of A277945.

%H R. H. Hardin, <a href="/A277940/b277940.txt">Table of n, a(n) for n = 1..210</a>

%F Empirical: a(n) = 17*a(n-1) -46*a(n-2) -74*a(n-3) +248*a(n-4) +365*a(n-5) -302*a(n-6) -2897*a(n-7) +586*a(n-8) +9050*a(n-9) +1379*a(n-10) -16481*a(n-11) -15496*a(n-12) +28568*a(n-13) +32667*a(n-14) -39070*a(n-15) -26031*a(n-16) +26346*a(n-17) +8108*a(n-18) -5448*a(n-19) -1536*a(n-20) for n>21

%e Some solutions for n=4

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

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

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

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

%Y Cf. A277945.

%K nonn

%O 1,2

%A _R. H. Hardin_, Nov 05 2016

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Last modified December 3 22:32 EST 2021. Contains 349468 sequences. (Running on oeis4.)