A263119 Number of (n+3) X (1+3) 0..1 arrays with each row divisible by 15 and column not divisible by 15, read as a binary number with top and left being the most significant bits.

14, 29, 59, 119, 238, 477, 955, 1911, 3822, 7645, 15291, 30583, 61166, 122333, 244667, 489335, 978670, 1957341, 3914683, 7829367, 15658734, 31317469, 62634939, 125269879, 250539758, 501079517, 1002159035, 2004318071, 4008636142

Offset

1,1

Links

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

Formula

Empirical: a(n) = 2*a(n-1) + a(n-4) - 2*a(n-5) = A265381(n+2).

Empirical g.f.: x*(14 + x + x^2 + x^3 - 14*x^4) / ((1 - x)*(1 + x)*(1 - 2*x)*(1 + x^2)). - Colin Barker, Jan 01 2019

Example

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

Crossrefs

Column 1 of A263124.

Sequence in context: A192836 A124681 A195145 * A196305 A041386 A041388

Adjacent sequences: A263116 A263117 A263118 * A263120 A263121 A263122

Keyword

nonn

Author

R. H. Hardin, Oct 10 2015

Status

approved