OFFSET
0,1
COMMENTS
All terms are divisible by 3.
FORMULA
a(n) = a(n-1)+a(n-5)-a(n-6). - Colin Barker, Feb 02 2013
G.f.: 3*(31*x^5 +2*x^4 +32*x^3 +32*x^2 +2*x +1) / ((x -1)^2*(x^4 +x^3 +x^2 +x +1)). - Colin Barker, Feb 02 2013
CROSSREFS
KEYWORD
nonn,easy
AUTHOR
Stefano Maruelli and Paola Paoloni (robotec(AT)netsurf.it), Mar 02 2008
EXTENSIONS
Edited by Charles R Greathouse IV, Nov 03 2009
STATUS
approved