A282856 Number of nX2 0..1 arrays with no 1 equal to more than one of its horizontal, vertical and antidiagonal neighbors.

4, 11, 31, 89, 251, 715, 2028, 5761, 16358, 46452, 131910, 374581, 1063696, 3020560, 8577449, 24357268, 69167021, 196412696, 557750593, 1583837157, 4497601906, 12771782030, 36267864414, 102989386002, 292457628811, 830488149997

Offset

1,1

Comments

Column 2 of A282862.

Links

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

Formula

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

Empirical: G.f.: -x*(1+x)*(x^3+x^2+3*x+4)/(-1+x+4*x^2+3*x^3+x^4+x^5) . - R. J. Mathar, Mar 02 2017

Example

Some solutions for n=4
..1..0. .0..1. .0..1. .0..0. .1..0. .1..1. .0..0. .0..1. .1..0. .0..0
..1..0. .1..0. .0..0. .1..0. .0..0. .0..0. .0..0. .1..0. .1..0. .0..0
..0..0. .0..0. .1..0. .1..0. .1..0. .1..0. .1..1. .0..1. .0..0. .1..0
..1..1. .1..1. .0..0. .0..0. .0..1. .0..1. .0..0. .0..0. .1..0. .0..1

Crossrefs

Cf. A282862.

Sequence in context: A027115 A077995 A276293 * A296572 A176573 A134597

Adjacent sequences: A282853 A282854 A282855 * A282857 A282858 A282859

Keyword

nonn

Author

R. H. Hardin, Feb 23 2017

Status

approved