There will be talks in October and November 2025. The seminar will take place in Aula INdAM at 12.
2025.10.17. Cathy Swaenepoel (Université Paris Cité)
Prime numbers with an almost prime reverse
Let b>1 be an integer. For any non-negative integer n, we call reverse of n in base b the integer obtained by reversing the digits of n. The existence of infinitely many prime numbers whose reverse is also prime is an open problem. In this talk, we will present a joint work with Cécile Dartyge and Joël Rivat, in which we show that there are infinitely many primes with an almost prime reverse. More precisely, we show that there exist an explicit positive integer Ω_b and a real number c_b>0 such that, for at least c_b*b^λ/λ² primes p ∈ [ b^{λ-1} , b^λ [, the reverse of p has at most Ω_b prime factors. Our proof is based on sieve methods and on obtaining a result in the spirit of the Bombieri-Vinogradov theorem concerning the distribution in arithmetic progressions of the reverse of prime numbers.
2025.11.21. Alberto Perelli (Università di Genova)
2025.11.28. Morten Risager (University of Copenhagen)
Past Events