A250608 Number of (n+1) X (5+1) 0..1 arrays with nondecreasing x(i,j)-x(i,j-1) in the i direction and nondecreasing x(i,j)-x(i-1,j) in the j direction.

247, 586, 1153, 2092, 3691, 6526, 11749, 21664, 40879, 78610, 153289, 301780, 597811, 1188838, 2369773, 4730440, 9450487, 18889210, 37765201, 75515644, 151014907, 302011726, 604003573, 1207985392, 2415947071, 4831868386

Offset

1,1

Links

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

Formula

Empirical: a(n) = 5*a(n-1) - 9*a(n-2) + 7*a(n-3) - 2*a(n-4).

Empirical: a(n) = 144*2^(n-1) + 42*n^2 + 69*n - 8.

Empirical g.f.: x*(247 - 649*x + 446*x^2 - 128*x^3) / ((1 - x)^3*(1 - 2*x)). - Colin Barker, Nov 15 2018

Example

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

Crossrefs

Column 5 of A250611.

Sequence in context: A318055 A261378 A063356 * A127349 A051153 A166399

Adjacent sequences: A250605 A250606 A250607 * A250609 A250610 A250611

Keyword

nonn

Author

R. H. Hardin, Nov 26 2014

Status

approved