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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.
1
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
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
KEYWORD
nonn
AUTHOR
R. H. Hardin, Oct 10 2015
STATUS
approved