Function: intnumstep
Section: sums
C-Name: intnumstep
Prototype: lp
Help: intnumstep(): gives the default value of m used by all intnum and sumnum
 routines, such that the integration step is 1/2^m.
Doc: give the value of $m$ used in all the
 \kbd{intnum} and \kbd{sumnum} programs, hence such that the integration
 step is equal to $1/2^m$.
