OFFSET
0,2
LINKS
R. H. Hardin, Table of n, a(n) for n = 0..215
FORMULA
Empirical: a(n) = a(n-1) + a(n-3) + 2*a(n-6) - 2*a(n-9) - a(n-10) - a(n-12) + a(n-15). - R. H. Hardin, Apr 29 2012.
Empirical g.f.: (1 + x + 2*x^2 + 2*x^3 + 2*x^4 + x^5 - 3*x^6 - 3*x^7 - 4*x^8 - 2*x^9 - x^10 + x^12 + x^13 + x^14) / ((1 - x)*(1 + x + x^2)*(1 - x - x^4 - 2*x^6 - x^7 + x^12)). - Colin Barker, Feb 22 2018
CROSSREFS
KEYWORD
nonn
AUTHOR
R. H. Hardin, Dec 24 2007
STATUS
approved