Several text files are available for viewing or downloading. These files have been updated every few years since 1995 (the current version was finished in August, 2020). Changes that will appear in the next update are listed in update file when we learn about them. We need the cooperation of the mathematical community to keep these data as accurate as possible, so please notify us of any errors or collaborations we have missed. The only thing you shouldn’t tell us about is a recent publication that will soon be listed on MathSciNet (Mathematical Reviews), since we’ll be sure to catch it at the next update anyway. Because of a change in website, some of these need format fixes, which will be done eventually.

Erdos0: This lists all people who have written a joint paper with Paul Erdös (i.e., who have Erdös number 1). It is in alphabetical order and shows the date of first collaboration, as well as the number of papers that each person has written with Erdös. There are currently 512 names on this list. For the curious, we note that this list includes two Browns, four Chens, two Chungs, two Fowlers, two Freuds, two Frieds, two Grahams, two Guys, two Herzogs, two Joos, two Montgomerys, two Murtys, two Sarkozys, two Harold Shapiros, two Smiths, two Steins, two Szekereses, three Taylors, two Wilsons, and two Zaks, but no author whose name begins with Q or X.

Erdos0d: This is similar to Erdos0, except that it is in order of date of first collaboration.

Erdos0p: This is similar to Erdos0, except that it is in order of number of joint papers (for those 202 people who have written more than one paper with Erdös).

Erdos1: This is an expanded version of Erdos0. For each person with Erdös number 1, the list of his/her collaborators (other than Erdös) is shown, in alphabetical order. These lists therefore contain other people with Erdös number 1, as well as all the people with Erdös number 2. The udpate file lists the changes that have been reported to us since the last update; these will be incorporated into all the lists at the next update, along with all the new publication links we find at that time.

Erdos2: This is a sort of inverse to Erdos1. It lists in alphabetical order all the people with Erdös number 2 (of which there are currently 12,600), and for each, his/her collaborators who have Erdös number 1.

ErdosA: This is an alphabetical list of all 13,113 people with Erdös number less than or equal to 2. It distinguishes between those people with Erdös number 1 and those with Erdös number 2 typographically (see next paragraph).

Notation: As complete a name as possible is given for each person. People with Erdös number 1 are shown in ALL CAPS; people with Erdös number 2 are shown with Normal Capitalization. Accents are omitted, but apostrophes and hyphens are included. Erdös coauthors known to be deceased are identified by an asterisk, but no attempt has been made to follow this convention for those with Erdös number 2. Numbers preceded by carets follow the convention used by Mathematical Reviews in MathSciNet to distinguish people with the same names. Further details, including ground rules for inclusion, are contained on the Information about the Erdös Number Project page.

See these statistical summaries of the number of Erdös number 1 coauthors for people with Erdös number 2, the number of Erdös number 1 coauthors for people with Erdös number 1, the total number of coauthors for people with Erdös number 1, the number of papers that Erdös’s coauthors have with him, and the number of new coauthors Paul Erdös added each year.

The data from the 2007 version of the lists were used to construct this textfile giving the adjacency lists for the induced subgraph of the collaboration graph on all Erdös coauthors, as of 2007. A very nice picture of the 2004 version of this graph has been produced by Valdis Krebs . A more recent picture was produced by Hadi Safari, who write "As can be seen, Erdős has collaborated directly or through an intermediary with different groups of scientists. Researchers in the field of graph and computer science (gold), specialists in number theory (pink), mathematicians in the field of set theory (blue), researchers in the field of computer engineering (green) and the isolated group of Peter Salamon and his colleagues are the main groups of these researchers. The names of researchers with more than 190 colleagues in the network (the first 10% of researchers) are written in the figure."

We also list Erdös number record holders as of 2020 (for example, which person with Erdös number 2 has the most coauthors with Erdös number 1?).

This page was last updated on October 15, 2021.