sci.math FAQ: Erdos Number

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Newsgroups: sci.math
From: alopez-o@neumann.uwaterloo.ca (Alex Lopez-Ortiz)
Subject: sci.math FAQ: Erdos Number
Summary: Part 30 of many, New version,
Message-ID: <DI76Mx.F32@undergrad.math.uwaterloo.ca>
Sender: news@undergrad.math.uwaterloo.ca (news spool owner)
Date: Fri, 17 Nov 1995 17:16:09 GMT
Reply-To: alopez-o@neumann.uwaterloo.ca


Archive-Name: sci-math-faq/erdos 
Last-modified: December 8, 1994
Version: 6.2




Erdos Number



   Form an undirected graph where the vertices are academics, and an edge
   connects academic X to academic Y if X has written a paper with Y .
   The Erdos number of X is the length of the shortest path in this graph
   connecting X with Erdos.

   Erdos has Erdos number 0. Co-authors of Erdos have Erdos number 1.
   Einstein has Erdos number 2, since he wrote a paper with Ernst Straus,
   and Straus wrote many papers with Erdos.

   The Extended Erdos Number applies to co-authors of Erdos. For People
   who have authored more than one paper with Erdos, their Erdos number
   is defined to be 1/# papers-co-authored. Ron Graham has the smallest,
   non-zero, Erdos number.

   Why people care about it?

   Nobody seems to have a reasonable answer...

   Who is Paul Erdos?

   Paul Erdos is an Hungarian mathematician. He obtained his PhD from the
   University of Manchester and has spent most of his efforts tackling
   "small" problems and conjectures related to graph theory,
   combinatorics, geometry and number theory.

   He is one of the most prolific publishers of papers; and is also and
   indefatigable traveller.



   References

   Caspar Goffman. And what is your Erdos number? American Mathematical
   Monthly, v. 76 (1969), p. 791.




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    alopez-o@barrow.uwaterloo.ca
    Tue Apr 04 17:26:57 EDT 1995