3 ms·Isn't that about co-authoring rather than teacher-pupil relationships?by TheCoelacanth 5y agoIsn't that about co-authoring rather than teacher-pupil relationships?sgillen 5y agoYes but the two are very related, a phd student will almost always publish papers with their advisor.bombcar 5y agoExactly - the smallest ones often go through teacher/pupil, and since almost all PhD mathematicians studied under a PhD it makes for a relatively small group.