cp's OEIS Frontend

A232370 Number of n X 2 0..3 arrays with every 0 next to a 1, every 1 next to a 2 and every 2 next to a 3 horizontally, diagonally or antidiagonally, and no adjacent values equal.

%I A232370 #7 Oct 05 2018 11:12:37
%S A232370 2,14,58,230,934,3794,15354,62266,252346,1022806,4145638,16802922,
%T A232370 68105158,276041834,1118844570,4534868126,18380594246,74499685134,
%U A232370 301959937342,1223895154962,4960655920226,20106384977054,81494609451994
%N A232370 Number of n X 2 0..3 arrays with every 0 next to a 1, every 1 next to a 2 and every 2 next to a 3 horizontally, diagonally or antidiagonally, and no adjacent values equal.
%H A232370 R. H. Hardin, <a href="/A232370/b232370.txt">Table of n, a(n) for n = 1..210</a>
%F A232370 Empirical: a(n) = 2*a(n-1) + 7*a(n-2) + 6*a(n-3) - 2*a(n-4) - 3*a(n-5) + 2*a(n-6) + a(n-7).
%F A232370 Empirical g.f.: 2*x*(1 + 5*x + 8*x^2 + 2*x^3 - 6*x^4 + x^5 + x^6) / ((1 + x)*(1 - 3*x - 4*x^2 - 2*x^3 + 4*x^4 - x^5 - x^6)). - _Colin Barker_, Oct 05 2018
%e A232370 Some solutions for n=7:
%e A232370 ..2..1....0..3....3..2....3..0....3..0....2..3....3..0....1..0....3..2....3..1
%e A232370 ..0..3....2..1....1..2....1..2....1..0....0..1....1..0....1..2....1..0....2..1
%e A232370 ..0..3....0..1....1..0....3..2....3..2....0..3....1..2....3..2....1..2....2..3
%e A232370 ..2..1....2..1....3..0....1..2....1..2....2..3....3..0....3..2....3..2....2..3
%e A232370 ..3..1....2..3....2..1....0..3....0..3....0..1....3..2....1..2....3..1....0..1
%e A232370 ..0..2....2..1....2..3....0..1....2..1....3..2....1..0....3..0....2..1....0..1
%e A232370 ..3..2....0..1....2..3....2..3....3..1....3..2....3..0....1..2....0..3....2..3
%Y A232370 Column 2 of A232376.
%K A232370 nonn
%O A232370 1,1
%A A232370 _R. H. Hardin_, Nov 23 2013