Erdős number | Hacker News Reader

Erdős number

en.wikipedia.org

16 pointsniyazpk22 comments

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.

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 ...

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

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 ...

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!

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.

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.

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.

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

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

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).

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 :)

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

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

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

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

I'm a 3, but totally by luck.

Also see http://spikedmath.com/056.html .

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.

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.

...Really? You find that absurd that he just made a simple goof to a fun problem like that? Believe me, Mathematicians are spending their time focused on much more important and difficult problems than the Monty Hall problem, so don't wonder too much.

And even by your own admission it involves no mathematical ability so why couldn't a Mathematician not get it, right?

That's a silly reasoning you have. One mistake doesn't invalid a persons entire integrity. All this proves, is that Erdős wan't god.

Reply on news.ycombinator.com