# Second Kind Degree Distribution

This table shows the distribution of the number of coauthors for the 401,445 authors in the Mathematical Reviews database when we consider only papers with exactly two authors. For example, 16,426 different mathematicians have exactly 3 coauthors under this restriction. In other words, this table gives the distribution of the degrees of the vertices in C', the collaboration graph of the second kind. The data are as of 2004.

**number of coauthors** **count** 0 166381 1 145872 2 34337 3 16426 4 9913 5 6670 6 4643 7 3529 8 2611 9 2032 10 1585 11 1303 12 1046 13 825 14 702 15 551 16 450 17 377 18 350 19 273 20 232 21 199 22 150 23 127 24 113 25 105 26 90 27 83 28 50 29 50 30 40 31 43 32 29 33 32 34 15 35 20 36 16 37 20 38 18 39 18 40 19 41 6 42 9 43 3 44 14 45 5 46 7 47 6 48 4 49 6 50 6 51 2 52 3 53 1 54 2 56 2 57 4 58 3 60 1 61 2 62 1 64 1 65 2 70 1 74 1 77 1 79 1 81 1 92 1 94 1 121 1 124 1 230 1

Of course the last line represents Paul Erdös: 230 people have an Erdös number of the second kind of 1, compared to over 500 people with an Erdös number of the first kind of 1.

This page was last updated on September 17, 2020.