A236120 - OEIS

%I #8 Oct 20 2018 11:02:32

%S 256,3096,37584,455808,5529360,67071552,813596592,9869111712,

%T 119714700240,1452167705472,17615140009200,213675837978720,

%U 2591938749790992,31440833634380352,381384791617780272

%N Number of (n+1) X (1+1) 0..3 arrays colored with the sets of distinct values in every 2 X 2 subblock.

%H R. H. Hardin, <a href="/A236120/b236120.txt">Table of n, a(n) for n = 1..210</a>

%F Empirical: a(n) = 6*a(n-1) + 59*a(n-2) + 164*a(n-3) + 264*a(n-4) + 96*a(n-5) - 144*a(n-6).

%F Empirical g.f.: 8*x*(32 + 195*x + 488*x^2 + 707*x^3 + 216*x^4 - 372*x^5) / (1 - 6*x - 59*x^2 - 164*x^3 - 264*x^4 - 96*x^5 + 144*x^6). - _Colin Barker_, Oct 20 2018

%e Some solutions for n=3:

%e ..3..2....3..3....2..1....3..0....1..2....2..2....2..2....3..3....0..1....2..2

%e ..1..2....1..1....1..0....1..3....1..3....2..3....3..2....3..3....3..1....1..3

%e ..3..0....1..0....0..1....3..3....0..3....3..0....0..0....0..3....2..1....0..0

%e ..3..1....0..2....3..1....3..3....3..2....1..3....1..2....1..3....1..2....2..1

%Y Column 1 of A236123.

%K nonn

%O 1,1

%A _R. H. Hardin_, Jan 19 2014