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 where
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.
[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.