A228680 Number of n X 5 binary arrays with no two ones adjacent horizontally, diagonally or antidiagonally.

13, 97, 809, 6737, 56549, 475809, 4008817, 33795201, 284980061, 2403420097, 20270798553, 170971640209, 1442058561397, 12163101107393, 102590452275041, 865306832676993, 7298499493581101, 61559793235182241, 519231197740651273

Offset

1,1

Comments

Column 5 of A228683.

Links

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

Formula

Empirical: a(n) = 12*a(n-1) -27*a(n-2) -32*a(n-3) +49*a(n-4) +20*a(n-5) -5*a(n-6).

Empirical g.f.: -x*(-13+59*x+4*x^2-64*x^3-15*x^4+5*x^5) / ( 1-12*x+27*x^2+32*x^3-49*x^4-20*x^5+5*x^6 ). - R. J. Mathar, Sep 02 2013

Example

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

Crossrefs

Cf. A228683.

Sequence in context: A049294 A198480 A126508 * A372770 A158795 A075899

Adjacent sequences: A228677 A228678 A228679 * A228681 A228682 A228683

Keyword

nonn

Author

R. H. Hardin, Aug 30 2013

Status

approved