A262473 Number of (3+1) X (n+1) 0..1 arrays with each row divisible by 3 and each column divisible by 5, read as a binary number with top and left being the most significant bits.

4, 9, 36, 121, 484, 1849, 7396, 29241, 116964, 466489, 1865956, 7458361, 29833444, 119311929, 477247716, 1908903481, 7635613924, 30542106169, 122168424676, 488672300601, 1954689202404, 7818751217209, 31275004868836, 125099997105721

Offset: 1

Author

R. H. Hardin, Sep 23 2015

Keywords

• nonn

Examples

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

Links

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

Crossrefs

Row 3 of A262472.

Formula

Empirical: a(n) = 4*a(n-1) + 5*a(n-2) - 20*a(n-3) - 4*a(n-4) + 16*a(n-5).

Empirical g.f.: x*(4 - 7*x - 20*x^2 + 12*x^3 + 16*x^4) / ((1 - x)*(1 + x)*(1 - 2*x)*(1 + 2*x)*(1 - 4*x)). - Colin Barker, Dec 31 2018