A283538 Number of nX3 0..1 arrays with no 1 equal to more than one of its horizontal, diagonal and antidiagonal neighbors.

7, 27, 127, 573, 2615, 11903, 54211, 246869, 1124239, 5119755, 23315255, 106177157, 483528423, 2201977727, 10027757771, 45666186717, 207962802543, 947057995307, 4312881128207, 19640765104365, 89443609136599, 407324214350687

Offset

1,1

Comments

Column 3 of A283543.

Links

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

Formula

Empirical: a(n) = 5*a(n-1) -a(n-2) -7*a(n-3) +10*a(n-4) +4*a(n-5) -8*a(n-6).

Empirical: G.f.: -x*(x-1)*(8*x^4 +12*x^3 -2*x^2 -x+7) /(1 -5*x +x^2 +7*x^3 -10*x^4 -4*x^5 +8*x^6) . - R. J. Mathar, Mar 11 2017

Example

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

Crossrefs

Cf. A283543.

Sequence in context: A147996 A267365 A034536 * A214459 A179597 A295209

Adjacent sequences: A283535 A283536 A283537 * A283539 A283540 A283541

Keyword

nonn

Author

R. H. Hardin, Mar 10 2017

Status

approved