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A274730 Number of 5 X n 0..2 arrays with no element equal to any value at offset (-1,-2) (-2,-1) or (-1,0) and new values introduced in order 0..2.

%I A274730 #8 Jan 30 2019 11:16:01
%S A274730 8,144,1040,9308,84948,771300,7016284,63780144,579907180,5272264616,
%T A274730 47934377596,435805897172,3962236677384,36023613993928,
%U A274730 327517339347916,2977702208511048,27072492754395896,246136048094770872
%N A274730 Number of 5 X n 0..2 arrays with no element equal to any value at offset (-1,-2) (-2,-1) or (-1,0) and new values introduced in order 0..2.
%H A274730 R. H. Hardin, <a href="/A274730/b274730.txt">Table of n, a(n) for n = 1..210</a>
%F A274730 Empirical: a(n) = 10*a(n-1) - a(n-2) - 80*a(n-3) + 133*a(n-4) - 49*a(n-5) - 16*a(n-6) + 4*a(n-7) for n>9.
%F A274730 Empirical g.f.: 4*x*(2 + 16*x - 98*x^2 - 77*x^3 + 841*x^4 - 1108*x^5 + 434*x^6 - 72*x^7 + 24*x^8) / ((1 - x)*(1 - 9*x - 8*x^2 + 72*x^3 - 61*x^4 - 12*x^5 + 4*x^6)). - _Colin Barker_, Jan 30 2019
%e A274730 Some solutions for n=4:
%e A274730 ..0..1..0..0. .0..1..0..2. .0..1..2..1. .0..1..0..2. .0..1..2..2
%e A274730 ..2..0..1..2. .1..0..1..0. .1..0..1..2. .1..0..1..0. .1..0..1..0
%e A274730 ..1..1..0..1. .2..1..2..1. .2..1..2..1. .0..2..0..1. .0..1..0..1
%e A274730 ..2..0..2..0. .1..0..1..0. .0..0..1..2. .1..0..2..0. .2..0..1..0
%e A274730 ..1..2..0..2. .2..1..0..1. .2..1..2..1. .2..2..0..1. .0..2..0..2
%Y A274730 Row 5 of A274728.
%K A274730 nonn
%O A274730 1,1
%A A274730 _R. H. Hardin_, Jul 03 2016