Frank Stephan's Erdoes-Number is Three
Thanks to Bill Gasarch for finding this number. Paul Erdoes is one of the most productive mathematicians having more than 500 coaouthors. The Erdoes Number of a person A is computed as the length of the shortest path from Paul Erdoes to the person A with respect to the graph of co-authors of scientific articles. Frank Stephan's Erdoes number is 3 and witnessed by the following publications.

• Paul Erdoes and Saharon Shelah: Separability properties of almost-disjoint families of sets. Israel Journal of Mathematics 12, 207-214 (1972).
  
• Uri Abraham, Saharon Shelah and Robert Solovay: Squares with diamonds and Souslin trees with special squares. Fundamenta Mathematicae 127, 133-162 (1987).
  
• Lance Fortnow, William Gasarch, Sanjay Jain, Efim Kinber, Martin Kummer, Stuart Kurtz, Mark Pleszkoch, Theodore Slaman, Robert Solovay and Frank Stephan: Extremes in the degrees of inferability. Annals of Pure and Applied Logic 66, 231-276 (1994).

Frank Stephan's Coauthors

1. Bahareh Afshari
   
2. Manindra Agrawal
   
3. Klaus Ambos-Spies
   
4. Jose L. Balcazar
   
5. Ganesh R. Baliga
   
6. George Barmpalias
   
7. Leonor Becerra Bonache
   
8. Richard Beigel
   
9. Laurent Bienvenu
   
10. Levke Bentzien
    
11. Bernd Borchert
    
12. Heinz Braun
    
13. Harry Buhrman
    
14. Cristian Calude
    
15. Lorenzo Carlucci
    
16. John Case
    
17. Barry Cooper
    
18. David Doty
    
19. Rod Downey
    
20. Peter Fejer
    
21. Henning Fernau
    
22. Santiago Figueira
    
23. Lance Fortnow
    
24. Johanna Franklin
    
25. Rusins Freivalds
    
26. Ziyuan Gao
    
27. William Gasarch
    
28. Alex Gavryushkin
    
29. Piotr Grabowski
    
30. Noam Greenberg
    
31. Valentina Harizanov
    
32. Nicholas Hay
    
33. Denis R. Hirschfeldt
    
34. Kejia Joyce Ho
    
35. Rupert Hoelzl
    
36. Gordon Hoi
    
37. Marcus Hutter
    
38. Sanjay Jain
    
39. Carl Jockusch
    
40. Susanne Kaufmann
    
41. Bakhadyr Khoussainov
    
42. Efim Kinber
    
43. Bjoern Kjos-Hanssen
    
44. Timo Koetzing
    
45. Thorsten Kraeling
    
46. Martin Kummer
    
47. Stuart A. Kurtz
    
48. Dietrich Kuske
    
49. Klaus-Joern Lange
    
50. Trong Dao Le
    
51. Andrew Lewis
    
52. Hongyang Li
    
53. Philip Long
    
54. Luc Longpre
    
55. Qinglong Luo
    
56. Eric Martin
    
57. Georgia Martin
    
58. Timothy McNicholl
    
59. Alexei Miasnikov
    
60. Wolfram Menzel
    
61. Wolfgang Merkle
    
62. Andrew Mitchell
    
63. Joseph S. Miller
    
64. Birzhan Moldagaliyev
    
65. Andrej A. Muchnik
    
66. Carl Mummert
    
67. Jochen Nessel
    
68. Phuong The Nguyen
    
69. Andre Nies
    
70. Yuh Shin Ong
71. Matthias Ott
    
72. Mark Pleszkoch
    
73. Alexander Raichev
    
74. Desh Ranjan
    
75. Jan Reimann
    
76. Ruediger Reischuk
    
77. Sasha Rubin
    
78. Marcus Schaefer
    
79. Tobias Scheffer
    
80. Philipp Schlicht
    
81. Samuel Seah
    
82. Pavel Semukhin
    
83. Arun Sharma
    
84. Stephen Simpson
    
85. Ted Slaman
    
86. Carl Smith
    
87. Robert Solovay
    
88. Ludwig Staiger
    
89. Dan Teng
90. Sebastiaan Terwijn
    
91. Pascal Tesson
    
92. Jason Teutsch
    
93. Denis Therien
    
94. P.S. Thiagarajan
    
95. Leen Torenvliet
    
96. Mahendran Velauthapillai
    
97. Yuri Ventsov
    
98. Volodya Vovk
    
99. Wei Wang
    
100. Rolf Wiehagen
     
101. Guohua Wu
     
102. Akihiro Yamamoto
     
103. Shaofa Yang
     
104. Yue Yang
     
105. Nan Ye
     
106. Ryo Yoshinaka
     
107. Liang Yu
     
108. Sandra Zilles
     
109. Thomas Zeugmann
     
110. Siyuan Zou.