Carlitz module analogues of Mersenne primes, Wieferich primes, and   certain prime elements in cyclotomic function fields
  In this paper, we introduce a Carlitz module analogue of Mersenne primes, and prove Carlitz module analogues of several classical results concerning Mersenne primes. In contrast to the classical case, we can show that there are infinitely many composite Mersenne numbers. We also study the acquaintances of Mersenne primes including Wieferich and non-Wieferich primes in the Carlitz module context that were first introduced by Dinesh Thakur. 
Dong Quan Ngoc Nguyen
math.NT