%I #8 Jan 31 2019 19:34:04

%S 5,16,45,129,373,1083,3148,9157,26623,77372,224857,653525,1899462,

%T 5520787,16046124,46637722,135551305,393976458,1145083415,3328158969,

%U 9673218248,28114986916,81715561920,237504397813,690301064559

%N Number of n X 3 0..2 arrays with no element equal to any value at offset (-2,-2) (-1,0) or (-1,1) and new values introduced in order 0..2.

%H R. H. Hardin, <a href="/A275126/b275126.txt">Table of n, a(n) for n = 1..210</a>

%F Empirical: a(n) = 3*a(n-1) - 2*a(n-2) + 4*a(n-3) + a(n-4) + 3*a(n-5) + 8*a(n-6) + a(n-7) - 3*a(n-8) - a(n-9) for n>10.

%F Empirical g.f.: x*(5 + x + 7*x^2 + 6*x^3 + 7*x^4 + 11*x^5 - 4*x^6 - 10*x^7 - 5*x^8 - x^9) / (1 - 3*x + 2*x^2 - 4*x^3 - x^4 - 3*x^5 - 8*x^6 - x^7 + 3*x^8 + x^9). - _Colin Barker_, Jan 31 2019

%e Some solutions for n=4:

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

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

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

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

%Y Column 3 of A275131.

%K nonn

%O 1,1

%A _R. H. Hardin_, Jul 17 2016