After working at the CNRS in 1986 and then at the University of Lyon, Christian Mauduit joined the Laboratoire de mathématiques discrètes in 1993, shortly after it was founded by Gérard Rauzy in Luminy. A specialist in number theory, he was particularly interested in equidistribution in sequences such as the Prouhet–Thue–Morse sequence. The term is used for any sequence defined by u0 = 0, u2n = un and u2n+1 = 1 – un. Such sequences have applications in mathematics—and in chess.
Together with Joël Rivat, Christian Mauduit proved that, on average, there are as many prime numbers whose decimal digits have an even sum as there are primes for which that sum is odd (this was Gelfond’s conjecture). In fact, he was an expert on the complexity of integer sequences and the representation of integers in different bases. He often worked collaboratively, particularly with the Hungarian mathematicians Pál Erdős and András Sárközy.
Christian Mauduit was also deeply committed to making mathematics accessible to the widest possible audience. He established a MATh.en.JEANS course at the university, organized workshops lasting several days under the name Hippocampe, directed the IREM of Aix-Marseille from 2006 to 2011, and founded and chaired the association Maths pour tous, which organizes numerous scientific events.
