A253156 Number of (n+1) X (5+1) 0..1 arrays with every 2 X 2 subblock diagonal minus antidiagonal sum nondecreasing horizontally and vertically.

181, 192, 201, 236, 308, 452, 740, 1316, 2468, 4772, 9380, 18596, 37028, 73892, 147620, 295076, 589988, 1179812, 2359460, 4718756, 9437348, 18874532, 37748900, 75497636, 150995108, 301990052, 603979940, 1207959716, 2415919268, 4831838372

Offset

1,1

Links

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

Formula

Empirical: a(n) = 3*a(n-1) -2*a(n-2) for n>5.

Empirical: a(n) = 9*2^(n-1) + 164 for n>3.

Empirical g.f.: x*(181 - 351*x - 13*x^2 + 17*x^3 + 2*x^4) / ((1 - x)*(1 - 2*x)). - Colin Barker, Dec 09 2018

Example

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

Crossrefs

Column 5 of A253159.

Sequence in context: A253439 A175789 A157747 * A139649 A159263 A159548

Adjacent sequences: A253153 A253154 A253155 * A253157 A253158 A253159

Keyword

nonn

Author

R. H. Hardin, Dec 28 2014

Status

approved