OFFSET
1,1
COMMENTS
Essentially identical to A022269. - R. J. Mathar, May 28 2008
LINKS
FORMULA
a(n)=(11*n^2+n)/2.
G.f.: x(6+5x)/(1-x)^3. - R. J. Mathar, Oct 23 2008
EXAMPLE
n=1: 2*n=2, 3*n=3, a(1)=6
PROG
(PARI) a(n)=(11*n^2+n)/2 \\ Charles R Greathouse IV, Jun 17 2017
CROSSREFS
KEYWORD
nonn,easy
AUTHOR
Dolmatov S. (aalma(AT)mail.ru), Jun 24 2003
STATUS
approved