Function: bnrisconductor
Section: number_fields
C-Name: bnrisconductor
Prototype: lGDGDG
Help: bnrisconductor(a1,{a2},{a3}): returns 1 if the modulus is the
 conductor of the subfield of the ray class field given by a1,a2,a3 (see
 bnrdisc), and 0 otherwise. Slightly faster than bnrconductor if this is the
 only desired result

