Jean-Louis Nicolas Explained

Jean-Louis Nicolas is a French number theorist.

He is the namesake (with Paul Erdős) of the Erdős–Nicolas numbers, and was a frequent co-author of Erdős,^[1] who would take over the desk of Nicolas' wife Anne-Marie (also a mathematician) whenever he would visit. Nicolas is also known for his research on integer partitions,^[2] and for his unusual proof that there exist infinitely many n for which

\varphi(n) < e ^{-\gamma} (n)/(loglog n) where \varphi(n) is Euler's totient function and γ is Euler's constant: he proved this bound unconditionally by providing two different proofs, one in the case that the Riemann hypothesis holds and another in the case that it fails.^[3]

Nicolas earned his Ph.D. in 1968 as a student of Charles Pisot. He works at Claude Bernard University Lyon 1.^[4]

A conference in honor of Nicolas' 60th birthday was held on January 14–19, 2002 at the Centre International de Rencontres Mathématiques in Marseille. The proceedings of the conference were published as a festschrift in The Ramanujan Journal.^[5]

Notes and References

1. http://www.oakland.edu/enp/Erdos0p List of collaborators of Erdős by number of joint papers
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4. http://math.univ-lyon1.fr/~nicolas/ Jean-Louis Nicolas
5. .