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

Author

R. H. Hardin, Aug 30 2013

Keywords

• nonn

Comments

Column 5 of A228683.

Examples

			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
		

Links

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

Crossrefs

Cf. A228683.

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