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%I #7 Feb 04 2019 14:24:38
%S 6,96,294,1176,4056,15000,54150,196566,714150,2589894,9405024,
%T 34129350,123887616,449661894,1632114294,5924052504,21502190976,
%U 78045783606,283279234776,1028207094936,3732040069656,13546029168150,49167456532134
%N Number of n X 4 0..2 arrays with no element equal to any value at offset (-2,0) (-1,2) or (0,-2) and new values introduced in order 0..2.
%H R. H. Hardin, <a href="/A275561/b275561.txt">Table of n, a(n) for n = 1..210</a>
%F Empirical: a(n) = 3*a(n-1) + 5*a(n-2) - 8*a(n-3) - 11*a(n-4) + 17*a(n-5) - 4*a(n-6) - 6*a(n-7) + 3*a(n-8) + 2*a(n-9) - a(n-10) for n>11.
%F Empirical g.f.: 6*x*(1 + 13*x - 4*x^2 - 23*x^3 - 18*x^4 + 43*x^5 - 16*x^6 - 13*x^7 + 10*x^8 + 5*x^9 - 3*x^10) / ((1 - 5*x + 6*x^2 - 4*x^3 + x^4)*(1 + 2*x - x^2 - 5*x^3 - x^4 + 2*x^5 + x^6)). - _Colin Barker_, Feb 04 2019
%e Some solutions for n=4:
%e ..0..1..2..0. .0..0..1..2. .0..0..1..1. .0..1..2..0. .0..1..2..0
%e ..0..2..1..1. .0..0..1..1. .0..0..1..2. .1..2..0..0. .1..1..0..2
%e ..2..2..0..1. .2..2..0..0. .2..1..0..0. .2..2..0..1. .2..0..1..2
%e ..2..0..0..2. .1..1..0..2. .1..2..0..1. .2..0..1..2. .0..0..1..1
%Y Column 4 of A275565.
%K nonn
%O 1,1
%A _R. H. Hardin_, Aug 01 2016
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