Jean-Louis Nicolas

Jean-Louis Nicolas is a French number theorist.

He is the namesake (with Paul Erdős) of the Erdős–Nicolas numbers,^[1][2] and was a frequent co-author of Erdős,^[3] who would take over the desk of Nicolas' wife Anne-Marie (also a mathematician) whenever he would visit.^[4] Nicolas is also known for his research on integer partitions,^[4] and for his unusual proof that there exist infinitely many n for which

${\displaystyle \varphi (n)<e^{-\gamma }{\frac {n}{\log \log n}}}$

where ${\displaystyle \varphi (n)}$ 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.^[5]

Nicolas earned his Ph.D. in 1968 as a student of Charles Pisot.^[6] He works at Claude Bernard University Lyon 1.^[7]

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.^[8]

References