OFFSET
1,1
LINKS
William A. Stein, Dimensions of the spaces S_k^{new}(Gamma_0(N))
William A. Stein, The modular forms database
Index entries for linear recurrences with constant coefficients, signature (1,1,-1).
FORMULA
Seems to be 6n - 3 + A062157(n-1). - Ralf Stephan, Feb 16 2004
G.f.: 3x-2*x^2*(-5-2*x+x^2) / ( (1+x)*(x-1)^2 ). - R. J. Mathar, Jul 15 2015
a(n) = 2*A007310(n) for n>1. - Philippe Deléham, Nov 23 2016
CROSSREFS
KEYWORD
nonn
AUTHOR
N. J. A. Sloane, Jul 10 2001
STATUS
approved