A262328 Number of (n+1) X (4+1) 0..1 arrays with each row and column divisible by 3, read as a binary number with top and left being the most significant bits.

11, 33, 351, 2399, 26131, 252097, 2767631, 29452071, 323841891, 3532758473, 38856792031, 426525918799, 4691681673011, 51580839266577, 567386112244911, 6240392439847991, 68644221256999171, 755059969459250713

Offset: 1

Author

R. H. Hardin, Sep 18 2015

Keywords

• nonn

Examples

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

Links

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

Crossrefs

Column 4 of A262332.

Formula

Empirical: a(n) = 11*a(n-1) + 48*a(n-2) - 528*a(n-3) - 579*a(n-4) + 6369*a(n-5) + 1612*a(n-6) - 17732*a(n-7).

Empirical g.f.: x*(11 - 88*x - 540*x^2 + 2762*x^3 + 6687*x^4 - 16120*x^5 - 17732*x^6) / ((1 - 2*x)*(1 + 2*x)*(1 - 11*x)*(1 - 13*x^2)*(1 - 31*x^2)). - Colin Barker, Dec 31 2018