A234790 Number of (n+1) X (2+1) 0..3 arrays with each 2 X 2 subblock having the number of clockwise edge increases less than or equal to the number of counterclockwise edge increases.

2504, 88072, 3015344, 102517088, 3479085232, 118012659040, 4002569571664, 135748608654080, 4603925743188432, 156142204831633856, 5295562097409075888, 179598936405126251936, 6091095934524947013424, 206579449021691878564640

Offset

1,1

Links

R. H. Hardin, Table of n, a(n) for n = 1..210

Formula

Empirical: a(n) = 47*a(n-1) - 485*a(n-2) + 1429*a(n-3) - 1056*a(n-4) + 208*a(n-5) - 40*a(n-6).

Empirical g.f.: 8*x*(313 - 3702*x + 11300*x^2 - 8422*x^3 + 1659*x^4 - 320*x^5) / (1 - 47*x + 485*x^2 - 1429*x^3 + 1056*x^4 - 208*x^5 + 40*x^6). - Colin Barker, Oct 16 2018

Example

Some solutions for n=2:
..3..1..0....0..1..2....0..2..0....0..2..2....1..0..2....3..2..3....1..0..2
..0..1..1....1..2..2....1..3..1....1..3..3....3..3..1....2..1..2....2..0..0
..1..3..0....1..2..0....1..2..3....0..1..1....0..3..1....2..2..3....3..0..0

Crossrefs

Column 2 of A234796.

Sequence in context: A045216 A205175 A205274 * A251858 A251854 A203055

Adjacent sequences: A234787 A234788 A234789 * A234791 A234792 A234793

Keyword

nonn

Author

R. H. Hardin, Dec 30 2013

Status

approved