A183703 - OEIS

%I #9 Apr 04 2018 10:48:07

%S 2472,108624,4760784,208772880,9154058448,401390133264,17600152230096,

%T 771732813754128,33838983410458320,1483773801471835152,

%U 65060601957611490000,2852781167483605911312,125088919099890142198992

%N Number of (n+1) X 3 0..3 arrays with every 2 X 2 subblock nonsingular.

%C Column 2 of A183710.

%H R. H. Hardin, <a href="/A183703/b183703.txt">Table of n, a(n) for n = 1..200</a>

%F Empirical: a(n) = 29*a(n-1) + 617*a(n-2) + 1587*a(n-3) - 4104*a(n-4).

%F Empirical g.f.: 24*x*(103 + 1539*x + 3561*x^2 - 9747*x^3) / (1 - 29*x - 617*x^2 - 1587*x^3 + 4104*x^4). - _Colin Barker_, Apr 04 2018

%e Some solutions for 5 X 3:

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

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

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

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

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

%Y Cf. A183710.

%K nonn

%O 1,1

%A _R. H. Hardin_, Jan 06 2011