OFFSET
1,2
FORMULA
a(n) = (n^4+2*n^3+5*n^2+4*n-12)/12. [adapted to offset by Gionata Neri, Feb 06 2021]
G.f.: x^2*(-4+5*x-4*x^2+x^3)/(x-1)^5. - Maksym Voznyy (voznyy(AT)mail.ru), Aug 10 2009
CROSSREFS
KEYWORD
nonn,easy
AUTHOR
EXTENSIONS
G.f. proposed by Maksym Voznyy checked and corrected by R. J. Mathar, Sep 16 2009
More terms from Erich Friedman
Offset corrected by Mohammad K. Azarian, Nov 19 2008
STATUS
approved