fact: Definition Bertrand_lim alpha beta (A : R) (I : R) := is_RInt_gen (fun x => powerRZ x alpha * (pow (ln x) beta)) (at_point A) (Rbar_locally p_infty) I.
imports: Coq(Reals ZArith Psatz Fourier_util) Flocq(Raux) Coquelicot(Coquelicot AutoDerive) mathcomp.ssreflect(ssreflect ssrfun ssrbool ssrnat bigop) Stdlib Coquelicot Xreal Interval