I hope this is an easy question but no so easy to be wiped out. I have asked few physical people (Profs) here in our department, and nobody has a clue. I'm reading this paper:

The locus of curves with prescribed automorphism group

and it uses following notation to represent a group:

G = (16, 13)

This is at the beginning of page 11. Shaska uses this notation in his other papers but I couldn't find an explanation for the kind of groups he's talking about. Could you please tell me exactly what's the meaning of this bracket notation? It could be a GAP thing but unfortunately I'm not a GAP person.

Thanks a lot.

yet. – Kevin O'Bryant Feb 22 '11 at 15:50