My excellent sister-in-law-in-law Virginia Transue, widow of a mathematician who was the son of a mathematician, mused on Facebook this morning about the extraordinarily prolific and collaborative Hungarian mathematician Paul Erdös:
Paul Erdös collaborated with so many people that mathematicians are often asked what their ERDÖS NUMBER is. If you wrote a paper with him your number was 1. If you wrote a paper with somebody who had written one with him it was 2… My Bill’s Erdös number was 2, his father’s was 3
From my 7/27/09 Language Log posting “Erdös?”:
There are linguists with Erdős numbers of 2 (András Kornai), 3 (Geoff Pullum, via András), and 4 (me, via Geoff)
November 18, 2025 at 11:01 am |
I believed I learned about this in the podcast post-broadcast chat after the BBC’s In Our Time did Erdös as a topic. That was a fun episode; I should re-listen (again!).
Oh, right! I see Colva Roney-Dougal was one of the participants. I enjoy her when she turns up.
https://www.bbc.co.uk/programmes/m001jc68
November 18, 2025 at 11:30 am |
PE was a fabulous subject: a tireless wide-ranging genius and a great eccentric to boot.
November 18, 2025 at 4:40 pm |
Matchscinet has an Erdös-number calculator at
https://mathscinet.ams.org/mathscinet/freetools/collab-dist
I’m not on it, but using collaborators, I’m 6.