A230180 Number of n X 4 0..2 arrays x(i,j) with each element horizontally or antidiagonally next to at least one element with value 2-x(i,j).

9, 159, 3411, 73857, 1603431, 34825803, 756450105, 16430979183, 356900507139, 7752307003185, 168389408761527, 3657619992450939, 79447894698990441, 1725703595660236095, 37484352623641494963, 814205113293390761697

Offset

1,1

Links

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

Formula

Empirical: a(n) = 26*a(n-1) - 97*a(n-2) + 89*a(n-3) - 18*a(n-4) + a(n-5).

Empirical g.f.: 3*x*(3 - 25*x + 50*x^2 - 69*x^3 + 9*x^4) / ((1 - x)*(1 - 25*x + 72*x^2 - 17*x^3 + x^4)). - Colin Barker, Sep 21 2018

Example

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

Crossrefs

Column 4 of A230184.

Sequence in context: A024122 A377450 A377447 * A361047 A360777 A309472

Adjacent sequences: A230177 A230178 A230179 * A230181 A230182 A230183

Keyword

nonn

Author

R. H. Hardin, Oct 11 2013

Status

approved