mathlib

fb28eac0 - feat(number_theory/bernoulli): Faulhaber's theorem (#6409)

feat(number_theory/bernoulli): Faulhaber's theorem (#6409) Co-authored-by Fabian Kruse Co-authored-by: Moritz Firsching <firsching@google.com> Co-authored-by: Benjamin Davidson <68528197+benjamindavidson@users.noreply.github.com>