A236149 - OEIS

%I #7 Oct 20 2018 14:20:25

%S 414,2502,16128,104436,676980,4389660,28462080,184549536,1196622156,

%T 7758928296,50309072208,326205221604,2115122387760,13714503742644,

%U 88925167552200,576592895708256,3738642012281784,24241443486843000

%N Number of (n+1) X (2+1) 0..2 arrays colored with the sets of distinct values in every 2 X 2 subblock.

%H R. H. Hardin, <a href="/A236149/b236149.txt">Table of n, a(n) for n = 1..210</a>

%F Empirical: a(n) = 3*a(n-1) + 19*a(n-2) + 24*a(n-3) - a(n-4) - 22*a(n-5) - 11*a(n-6) - 2*a(n-7) - 2*a(n-8).

%F Empirical g.f.: 6*x*(69 + 210*x + 126*x^2 - 237*x^3 - 399*x^4 - 171*x^5 - 43*x^6 - 27*x^7) / (1 - 3*x - 19*x^2 - 24*x^3 + x^4 + 22*x^5 + 11*x^6 + 2*x^7 + 2*x^8). - _Colin Barker_, Oct 20 2018

%e Some solutions for n=4:

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

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

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

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

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

%Y Column 2 of A236155.

%K nonn

%O 1,1

%A _R. H. Hardin_, Jan 19 2014