A200572 Number of n X 1 0..2 arrays with no average of any element and its horizontal and vertical neighbors equal to one.

2, 6, 10, 22, 52, 114, 260, 600, 1374, 3162, 7290, 16796, 38722, 89296, 205916, 474882, 1095218, 2525902, 5825564, 13435770, 30987588, 71468368, 164831598, 380160714, 876787090, 2022186212, 4663888698, 10756605360, 24808602932, 57217567106

Offset

1,1

Comments

Column 1 of A200579.

Links

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

Formula

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

Empirical g.f.: 2*x*(1 + x)^2*(1 - x - x^2) / (1 - 2*x - x^2 - x^3 + 3*x^4 + 2*x^5). - Colin Barker, Mar 02 2018

Example

Some solutions for n=5:
..2....2....0....2....1....0....0....1....0....0....1....0....2....0....2....0
..1....2....0....2....0....0....1....0....0....0....0....0....2....0....2....1
..1....0....2....1....1....1....0....0....0....0....0....2....1....1....1....0
..0....0....2....1....1....1....0....2....0....2....0....2....1....0....2....0
..1....0....1....0....2....0....1....2....1....2....1....2....2....0....2....0

Crossrefs

Cf. A200579.

Sequence in context: A167512 A055895 A125527 * A342136 A049750 A295139

Adjacent sequences: A200569 A200570 A200571 * A200573 A200574 A200575

Keyword

nonn

Author

R. H. Hardin, Nov 19 2011

Status

approved