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A231397 Number of (1+1) X (n+1) 0..2 arrays with no element unequal to a strict majority of its horizontal, diagonal and antidiagonal neighbors, with values 0..2 introduced in row major order.

%I A231397 #11 Sep 29 2018 03:01:00
%S A231397 3,7,14,33,78,189,482,1225,3238,8565,23114,62657,171342,470573,
%T A231397 1297330,3586745,9934454,27559269,76525210,212662577,591289630,
%U A231397 1644693789,4576035586,12734509097,35443628358,98659578197,274645954794
%N A231397 Number of (1+1) X (n+1) 0..2 arrays with no element unequal to a strict majority of its horizontal, diagonal and antidiagonal neighbors, with values 0..2 introduced in row major order.
%H A231397 R. H. Hardin, <a href="/A231397/b231397.txt">Table of n, a(n) for n = 1..210</a>
%F A231397 Empirical: a(n) = 4*a(n-1) + a(n-2) - 16*a(n-3) + 4*a(n-4) + 24*a(n-5) - 16*a(n-6).
%F A231397 Empirical g.f.: x*(3 - 5*x - 17*x^2 + 18*x^3 + 32*x^4 - 32*x^5) / ((1 - x)*(1 - 2*x)*(1 - x - 6*x^2 + 8*x^4)). - _Colin Barker_, Sep 28 2018
%e A231397 Some solutions for n=5:
%e A231397 ..0..1..1..1..1..2....0..1..0..1..0..0....0..0..1..1..0..0....0..0..1..1..0..0
%e A231397 ..0..0..1..1..2..2....1..0..1..0..1..1....0..0..1..1..1..0....0..0..1..1..0..0
%Y A231397 Row 1 of A231396.
%K A231397 nonn
%O A231397 1,1
%A A231397 _R. H. Hardin_, Nov 08 2013