mathlib

6a033cb3 - feat(number_theory/bernoulli): Fourier coefficients of Bernoulli polynomials (#17990)

feat(number_theory/bernoulli): Fourier coefficients of Bernoulli polynomials (#17990) Add the integral formula `∫ x in 0..1, exp(-2 * π * I * n * x) * B k x = -k! / (2 * π * I * n) ^ k`, where `B k` is the `k`-th Bernoulli polynomial. Co-authored-by: Junyan Xu <junyanxu.math@gmail.com>