Function: elllseries
Section: elliptic_curves
C-Name: elllseries
Prototype: GGDGp
Help: elllseries(E,s,{A=1}): L-series at s of the elliptic curve E, where A
 a cut-off point close to 1.
Doc:
 $E$ being an \var{sell} as output by
 \kbd{ellinit}, this computes the value of the L-series of $E$ at $s$. It is
 assumed that $E$ is defined over $\Q$, not necessarily minimal. The optional
 parameter $A$ is a cutoff point for the integral, which must be chosen close
 to 1 for best speed. The result must be independent of $A$, so this allows
 some internal checking of the function.

 Note that if the conductor of the curve is large, say greater than $10^{12}$,
 this function will take an unreasonable amount of time since it uses an
 $O(N^{1/2})$ algorithm.
