
Erdős number - niyazpk
http://en.wikipedia.org/wiki/Erd%C5%91s_number
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jedbrown
A former professor of mine grew up with Paul Erdös frequently living at her
house. Her father is a prominent graph theorist and has 50 papers with Paul
Erdös. Ordinarily she would have Erdös number 2 through several papers with
her dad, but has been granted an honorary 1.5 because she also washed his
clothes.

~~~
RiderOfGiraffes
Interestingly, there are three people who have co-authored 50 or more papers
with Erdos. The most prolific is not a graph theorist, the next is also not
thought of as a graph theorist.

The third is listed as having published exactly 50 papers with Erdos, and _is_
a graph theorist. More, there is a female math professor with the same
surname, also in combinatorics and graph theory.

Now I can guess where you did your university work.

Fun game to play ...

~~~
jedbrown
Excellent detective work Watson, but there are more direct ways.

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RiderOfGiraffes
That link didn't work for me - locale problems - but this one does:

<http://en.wikipedia.org/wiki/Erd%25C5%2591s_number>

I have an Erdos number of 2, and remember being unreasonably delighted to
discover I have an Edros number of the second type of only 3. I thought it
would be much bigger.

Not that it really means anything, but it would now be cool to appear as an
extra in a Kevin Bacon movie ...

~~~
cperciva
Lucky you -- my Erdos number is 3, in part because I didn't start publishing
until after Erdos died. I do have independent length-3 paths through four
different people, though.

Amusingly, my Erdos number of the second kind is infinite: I've written
single-author papers and three-author papers, but no two-author papers!

~~~
RiderOfGiraffes
It's still easy enough to get a number of the first kind of 2, there are
hundreds of active mathematicians with EN=1. You need to find one who shares
an interest and then publish something serious with them.

Ditto the type 2. If we found something that was worth getting into a journal
at least you'd get EN(2)=4.

~~~
cperciva
_there are hundreds of active mathematicians with EN=1_

True, but the ones who are still active are generally quite senior, and
wouldn't be interested in working with a nobody like me.

~~~
RiderOfGiraffes
Depends (almost) entirely on what you're choosing to do. If you find something
in the area of interest of one of them, then make a substantial contribution,
then ask if they can help tidy of the details, it's plausible that it could
happen. You'd need to make it a goal, and it's not clear that it's really
worth it.

John Brillhart, Richard Guy, Robin Wilson, Peter Winkler and Ron Graham all
come to mind, mind you'd need time, effort, math and social engineering.

~~~
cperciva
That's way too much work to do just to reduce my Erdos number. :-)

~~~
RiderOfGiraffes
Absolutely. Not impossible, just not really worth the effort.

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morganpyne
For those of you unfamiliar with Paul Erdős and who are interested in learning
more, I highly recommend the biography "The Man Who Loved Only Numbers", by
Paul Hoffman. He was such a quirky and unique character that his story makes a
great read (even for non-mathematicians).

~~~
riffraff
an interesting and much lighter source of information is the movie/documentary
from 1993 called "N Is a Number: A Portrait of Paul Erdős" though IMDB seems
to have it with a short accent :)

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markkat
Ha. I know Grossman, the guy who runs the The Erdös Number Project. He used to
publish with my friend's father.

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jonp
If there were similar named numbers for co-founders or co-investors who should
be given a number of zero?

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pilif
Knowing of the Erdős number is the requirement for understanding
<http://xkcd.com/599/>

~~~
troels
Conversely, I learned about Erdős from that comic, initially.

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geophile
I'm a 3, but totally by luck.

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Muzza
Also see <http://spikedmath.com/056.html> .

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mingdingo
For all his brilliance, Erdos was unable to answer the Monty Hall Problem
correctly: <http://en.wikipedia.org/wiki/Monty_Hall_problem>.

For those who don't know it, the problem requires no math except a _very_
basic grasp of probability. Personally, I find it somewhat absurd that you can
be considered a mathematical legend but still miss that problem. I think it
even took Erdos some time (months) to accept the solution, but I don't have a
citation for that.

He's not alone, either. Lots of mathematicians miss that problem, which makes
me wonder about the fundamentals of a Math education.

~~~
hugh3
I really hate to start yet another Monty Hall Problem discussion, but it's
worth noting that the Monty Hall Problem is often ambiguously phrased -- it's
not specified whether the host _has_ to open a door to show a goat or not. If
Erdos got confused, it's probably because he heard an ambiguous version.

