A232070 Number of (n+1) X (2+1) 0..1 arrays with every element equal to some horizontal, diagonal or antidiagonal neighbor, with top left element zero.

15, 87, 602, 3985, 26713, 178484, 1193537, 7979619, 53352090, 356709629, 2384952501, 15945724308, 106612681357, 712809462455, 4765824578786, 31864172723641, 213042987115297, 1424399583243252, 9523496644232169

Offset

1,1

Links

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

Formula

Empirical: a(n) = 5*a(n-1) + 11*a(n-2) + 2*a(n-3) - 8*a(n-5).

Empirical g.f.: x*(15 + 12*x + 2*x^2 - 12*x^3 - 8*x^4) / (1 - 5*x - 11*x^2 - 2*x^3 + 8*x^5). - Colin Barker, Oct 03 2018

Example

Some solutions for n=6:
..0..0..0....0..1..0....0..1..0....0..0..0....0..1..0....0..0..0....0..0..0
..1..1..0....1..0..0....0..0..1....1..1..0....0..0..1....0..1..0....1..0..0
..0..1..1....0..0..0....0..1..1....1..0..0....0..0..0....1..0..0....1..1..1
..1..0..1....0..0..0....1..0..1....1..1..1....1..1..0....0..1..0....0..0..0
..0..1..0....0..1..0....1..0..0....1..1..1....0..0..0....1..1..1....1..0..1
..0..1..0....1..0..1....1..1..1....0..0..0....1..0..0....0..0..1....1..1..0
..1..0..1....1..1..0....0..0..0....0..0..0....0..1..1....0..1..0....1..1..1

Crossrefs

Column 2 of A232076.

Sequence in context: A309922 A302948 A230676 * A219598 A241433 A220150

Adjacent sequences: A232067 A232068 A232069 * A232071 A232072 A232073

Keyword

nonn

Author

R. H. Hardin, Nov 17 2013

Status

approved