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%I #7 Feb 04 2019 09:08:17
%S 14,64,396,2564,17036,114184,767400,5162348,34738608,233788948,
%T 1573443364,10589696164,71271786592,479680852000,3228399847820,
%U 21728128472720,146237025626140,984220433953220,6624108115567212
%N Number of 4 X n 0..2 arrays with no element equal to any value at offset (-2,-1) (-2,1) or (-1,-1) and new values introduced in order 0..2.
%H R. H. Hardin, <a href="/A275268/b275268.txt">Table of n, a(n) for n = 1..210</a>
%F Empirical: a(n) = 8*a(n-1) - 7*a(n-2) - 9*a(n-3) - 8*a(n-4) - 12*a(n-5) + 16*a(n-6) for n>7.
%F Empirical g.f.: 2*x*(7 - 24*x - 9*x^2 - 15*x^3 - 8*x^4 + 44*x^5 - 16*x^6) / (1 - 8*x + 7*x^2 + 9*x^3 + 8*x^4 + 12*x^5 - 16*x^6). - _Colin Barker_, Feb 04 2019
%e Some solutions for n=4:
%e ..0..1..0..1. .0..0..1..1. .0..0..0..1. .0..1..1..1. .0..1..0..2
%e ..2..2..0..2. .0..1..1..2. .1..1..1..1. .0..1..2..2. .0..1..0..1
%e ..2..1..0..2. .1..2..2..2. .1..2..2..2. .0..2..2..0. .2..1..0..1
%e ..1..1..0..1. .2..2..0..0. .2..0..0..0. .0..1..0..0. .2..1..2..2
%Y Row 4 of A275266.
%K nonn
%O 1,1
%A _R. H. Hardin_, Jul 21 2016