OFFSET
1,1
COMMENTS
Column 3 of A222027.
LINKS
R. H. Hardin, Table of n, a(n) for n = 1..210
FORMULA
Empirical: a(n) = a(n-1) + 2*a(n-3) - a(n-4) + a(n-8) - a(n-9) + a(n-11) - a(n-12) - 2*a(n-14) + a(n-15).
Empirical g.f.: x*(2 + x + x^2 - x^3 - 2*x^8 - 2*x^11 - x^12 - x^13 + x^14) / ((1 - x)*(1 + x + x^2)*(1 - x - x^3 - x^6 - x^8 - 2*x^11 + x^12)). - Colin Barker, Aug 14 2018
EXAMPLE
Some solutions for n=7, one extended zero followed by filtered positions:
..0....0....0....0....0....0....0....0....0....0....0....0....0....0....0....0
..0....0....0....0....0....0....0....0....0....0....0....0....0....0....0....0
..0....0....0....0....0....0....0....0....0....0....0....0....0....0....0....0
..1....1....0....0....0....1....1....0....1....0....1....0....1....0....0....1
..0....0....0....0....0....0....0....0....0....0....0....0....0....1....1....0
..0....1....0....0....1....0....1....0....0....0....0....1....0....0....0....1
..0....0....1....1....0....1....0....0....0....0....1....0....0....1....0....0
..1....0....0....0....1....0....0....1....0....0....0....0....0....0....0....0
..0....0....1....0....0....1....1....0....0....0....0....0....1....0....0....0
..0....1....0....0....0....0....0....0....0....0....1....1....0....0....1....0
..0....0....0....0....0....0....0....0....0....0....0....0....0....0....0....0
CROSSREFS
KEYWORD
nonn
AUTHOR
R. H. Hardin, Feb 05 2013
STATUS
approved