A232332 - OEIS

%I #8 Oct 04 2018 11:50:28

%S 10,82,628,4906,38986,312276,2510674,20221026,162993780,1314329242,

%T 10600203674,85498798420,689639995266,5562789156722,44871062410868,

%U 361944328742026,2919563842456426,23550196645340116,189963983083385394

%N Number of n X 5 0..2 arrays with every 0 next to a 1 and every 1 next to a 2 horizontally or antidiagonally, with no adjacent elements equal.

%H R. H. Hardin, <a href="/A232332/b232332.txt">Table of n, a(n) for n = 1..210</a>

%F Empirical: a(n) = 11*a(n-1) - 21*a(n-2) - 20*a(n-3) - 12*a(n-4) for n>5.

%F Empirical g.f.: 2*x*(5 - 14*x - 32*x^2 - 40*x^3 - 16*x^4) / (1 - 11*x + 21*x^2 + 20*x^3 + 12*x^4). - _Colin Barker_, Oct 04 2018

%e Some solutions for n=6:

%e ..0..1..2..1..0....0..1..2..1..2....0..1..2..1..0....0..1..2..1..0

%e ..2..1..0..1..2....0..1..2..1..2....0..1..2..1..2....2..1..2..1..2

%e ..2..1..2..1..0....0..1..2..1..2....0..1..0..1..0....0..1..2..1..0

%e ..0..1..2..1..0....2..1..0..1..0....2..1..2..1..0....0..1..0..1..2

%e ..0..1..2..1..0....2..1..2..1..0....0..1..0..1..2....0..1..2..1..0

%e ..0..1..0..1..2....0..1..0..1..2....2..1..0..1..0....0..1..0..2..1

%Y Column 5 of A232335.

%K nonn

%O 1,1

%A _R. H. Hardin_, Nov 22 2013