A231524 Number of 2 X n 0..1 arrays with no element less than a strict majority of its horizontal, diagonal and antidiagonal neighbors.

4, 10, 34, 107, 342, 1069, 3381, 10689, 33808, 106804, 337525, 1066772, 3371763, 10656541, 33680325, 106448622, 336438736, 1063336915, 3360744286, 10621851017, 33571065345, 106103576857, 335347363656, 1059887498352, 3349844553061

Offset: 1

Author

R. H. Hardin, Nov 10 2013

Keywords

• nonn

Examples

			Some solutions for n=7:
  0 1 0 0 0 0 1      1 0 0 0 0 0 1      0 0 0 1 0 0 0
  1 0 0 1 0 1 1      1 0 0 1 0 0 1      0 0 1 0 0 1 0
		

Links

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

Crossrefs

Row 2 of A231523.

Formula

Empirical: a(n) = 4*a(n-1) - 3*a(n-2) + a(n-3) + 6*a(n-4) - 18*a(n-5).

Empirical g.f.: x*(4 - 6*x + 6*x^2 - 3*x^3 - 18*x^4) / (1 - 4*x + 3*x^2 - x^3 - 6*x^4 + 18*x^5). - Colin Barker, Sep 29 2018