A228751 Number of n X 5 binary arrays with top left element equal to 1 and no two ones adjacent horizontally or antidiagonally.

5, 50, 482, 4599, 43862, 418370, 3990739, 38067290, 363121586, 3463797759, 33040991486, 315176359538, 3006451507579, 28678390419458, 273561730649282, 2609491655262279, 24891810279661862, 237441732282894050

Offset: 1

Author

R. H. Hardin, Sep 02 2013

Keywords

• nonn

Examples

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

Links

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

Crossrefs

Column 5 of A228754.

Formula

Empirical: a(n) = 13*a(n-1) - 36*a(n-2) + 29*a(n-3) - 5*a(n-4) for n>5.

Empirical g.f.: x*(5 - 15*x + 12*x^2 - 12*x^3 + 2*x^4) / ((1 - x)*(1 - 12*x + 24*x^2 - 5*x^3)). - Colin Barker, Sep 12 2018