OFFSET
1,1
LINKS
William A. Stein, Dimensions of the spaces S_k(Gamma_0(N)).
William A. Stein, The modular forms database
FORMULA
Conjectures from Colin Barker, Jun 10 2019: (Start)
G.f.: x*(8 + 11*x + x^2) / (1 - x)^2.
a(n) = 2*a(n-1) - a(n-2) for n>3.
a(n) = 20*n-13 for n>1.
(End)
CROSSREFS
KEYWORD
nonn
AUTHOR
N. J. A. Sloane, Jul 08 2001
STATUS
approved