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A231420 Number of (1+1) X (n+1) 0..2 arrays with no element equal to a strict majority of its horizontal, diagonal and antidiagonal neighbors, with values 0..2 introduced in row major order.

%I A231420 #8 Sep 28 2018 15:19:28
%S A231420 9,71,514,3838,28486,212060,1578180,11748804,87465304,651171800,
%T A231420 4847955288,36093104816,268714229264,2000587354768,14894452176096,
%U A231420 110889806477664,825579209354848,6146471657514944,45760738536130624
%N A231420 Number of (1+1) X (n+1) 0..2 arrays with no element equal to a strict majority of its horizontal, diagonal and antidiagonal neighbors, with values 0..2 introduced in row major order.
%H A231420 R. H. Hardin, <a href="/A231420/b231420.txt">Table of n, a(n) for n = 1..210</a>
%F A231420 Empirical: a(n) = 8*a(n-1) + 4*a(n-2) - 58*a(n-3) - 24*a(n-4) + 40*a(n-5) - 16*a(n-6).
%F A231420 Empirical g.f.: x*(9 - x - 90*x^2 - 36*x^3 + 60*x^4 - 24*x^5) / (1 - 8*x - 4*x^2 + 58*x^3 + 24*x^4 - 40*x^5 + 16*x^6). - _Colin Barker_, Sep 28 2018
%e A231420 Some solutions for n=6:
%e A231420 ..0..0..1..2..0..0..2....0..0..1..1..0..2..0....0..1..2..2..1..0..2
%e A231420 ..1..2..0..2..2..0..1....1..1..2..2..1..1..1....0..1..0..1..1..2..2
%Y A231420 Row 1 of A231419.
%K A231420 nonn
%O A231420 1,1
%A A231420 _R. H. Hardin_, Nov 08 2013