Green’s Functions and Euler’s Formula for ζ (2n) Book Chapter

Ashbaugh, MS, Gesztesy, F, Hermi, L et al. (2021). Green’s Functions and Euler’s Formula for ζ (2n) . 348 27-45. 10.1007/978-3-030-68490-7_3

cited authors

  • Ashbaugh, MS; Gesztesy, F; Hermi, L; Kirsten, K; Littlejohn, L; Tossounian, H

authors

abstract

  • In this note, we calculate the Green’s function for the linear operator (D )n, whereD is the one-dimensional Dirichlet Laplacian in L2 ((0, 1); dx) defined byD f = − f′′ with (Dirichlet) boundary conditions f (0) = f (1) = 0. As a consequence of this computation, we obtain Euler’s formula ζ (2n) =∑k∈N k−2n =(−1)n−1 22n−1 π2n B2n, n ∈ N, (2n)! where ζ (·) denotes the Riemann zeta function and Bn is the nth Bernoulli number. This generalizes the example given by Grieser [29] for n = 1. In addition, we derive its z-dependent generalization for z ∈ C\{(kπ)2n}k∈N, ∑ k∈N [ (kπ)2n − z] [ −1 1= n − 2nz ∑n−1 j =0 ω1/2 j z1/(2n) cot(ω1/2 j z1/(2n))], n ∈ N, where ωj = e2πi j /n, 0 ≤ j ≤ n − 1, represent the nth roots of unity. In this context we also derive the Green’s function of((D )n − z I)−1, n ∈ N.

publication date

  • January 1, 2021

Digital Object Identifier (DOI)

International Standard Book Number (ISBN) 13

start page

  • 27

end page

  • 45

volume

  • 348