cp's OEIS Frontend

A230676 Number of 2 X n 0..2 arrays x(i,j) with each element horizontally, diagonally or antidiagonally next to at least one element with value 2-x(i,j).

%I A230676 #8 Sep 22 2018 10:53:25
%S A230676 0,15,87,513,3387,21933,141411,913245,5898099,38088477,245968275,
%T A230676 1588424445,10257784563,66243081501,427786930899,2762577674301,
%U A230676 17840272397235,115209545904477,744004305214611,4804657476983421
%N A230676 Number of 2 X n 0..2 arrays x(i,j) with each element horizontally, diagonally or antidiagonally next to at least one element with value 2-x(i,j).
%H A230676 R. H. Hardin, <a href="/A230676/b230676.txt">Table of n, a(n) for n = 1..210</a>
%F A230676 Empirical: a(n) = 5*a(n-1) + 6*a(n-2) + 20*a(n-3) + 12*a(n-4) + 8*a(n-5).
%F A230676 Empirical g.f.: 3*x^2*(5 + 4*x - 4*x^2) / (1 - 5*x - 6*x^2 - 20*x^3 - 12*x^4 - 8*x^5). - _Colin Barker_, Sep 22 2018
%e A230676 Some solutions for n=3:
%e A230676 ..0..2..2....0..0..2....1..1..1....0..2..0....0..0..2....0..2..0....2..2..2
%e A230676 ..0..0..0....2..2..2....1..2..0....0..2..0....2..2..0....0..1..1....0..0..2
%Y A230676 Row 2 of A230675.
%K A230676 nonn
%O A230676 1,2
%A A230676 _R. H. Hardin_, Oct 27 2013