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Erdős number (Definition)

The shortest number of collaborations with other mathematicians through which a particular mathematician can be connected to Paul Erdős is the Erdős number of that mathematician. For example, N. J. A. Sloane coauthored Sphere Packings, Lattices and Groups with John Horton Conway. In turn, Conway coauthored a paper with Erdős in 1979, thus Sloane's Erdős number is 2. Since Erdős died in 1996, 2 is the lowest Erdős number a mathematician working today can achieve.

One way to visualize the Erdős number is by drawing up a collaboration graph $ G$ whose vertex set consists of all persons, where two vertices $ x$ and $ y$ are connected by an edge if and only if $ x$ and $ y$ have a joint publication. Then the Erdős number of a person $ x$ is the distance in $ G$ (possibly infinity) of $ x$ from Erdős.



"Erdős number" is owned by Mravinci. [ owner history (1) ]
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See Also: Erdős number

Other names:  Erdos number, Erdös number

Attachments:
list of mathematicians with Erdős number 1 (Topic) by Mravinci
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Cross-references: infinity, distance, edge, vertices, vertex, graph, John Horton Conway, groups, sphere, connected
There are 40 references to this entry.

This is version 4 of Erdős number, born on 2006-09-18, modified 2006-09-19.
Object id is 8376, canonical name is ErdHosNumber.
Accessed 2036 times total.

Classification:
AMS MSC: 01A60 (History and biography :: History of mathematics and mathematicians :: 20th century)
 01A61 (History and biography :: History of mathematics and mathematicians :: Twenty-first century)
Pending Errata and Addenda
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Discussion
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Erdos's work is useless by martin2000 on 2007-06-19 08:07:52
Erdos's work on numbers is useless. He doesn't even had a university degree!
The Erdos numbers are just a propaganda! What are they important for? For NOTHING!
For every scientist X you can design X numbers, but they are useless as Erdos numbers!

Martin
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Erdos number for physicists by PrimeFan on 2007-06-12 20:30:13
I wonder which physicist gives other physicists the most connections for Erdos numbers.
[ reply | up ]
Erdos duplication by PrimeFan on 2006-09-20 14:24:32
The object with canonical name "ErdHosNumber" duplicates the object with the canonical name "ErdoesNumber". Is it at all possible to merge the two objects, and to take the best of each in the process?
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