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24 Bernoulli and Euler PolynomialsApplications

§24.17 Mathematical Applications

Contents
  1. §24.17(i) Summation
  2. §24.17(ii) Spline Functions
  3. §24.17(iii) Number Theory

§24.17(i) Summation

Euler–Maclaurin Summation Formula

See §2.10(i). For a generalization see Olver (1997b, p. 284).

Boole Summation Formula

Let 0\leq h\leq 1 and a,m, and n be integers such that n>a, m>0, and f^{(m)}(x) is absolutely integrable over [a,n]. Then with the notation of §24.2(iii)

where

Calculus of Finite Differences

See Milne-Thomson (1933), Nörlund (1924), or Jordan (1965). For a more modern perspective see Graham et al. (1994).

§24.17(ii) Spline Functions

Euler Splines

Let \mathcal{S}_{n} denote the class of functions that have n-1 continuous derivatives on \mathbb{R} and are polynomials of degree at most n in each interval (k,k+1), k\in\mathbb{Z}. The members of \mathcal{S}_{n} are called cardinal spline functions. The functions

24.17.3 S_{n}(x)=\frac{\widetilde{E}_{n}\left(x+\tfrac{1}{2}n+\tfrac{1}{2}\right)}{%
\widetilde{E}_{n}\left(\tfrac{1}{2}n+\tfrac{1}{2}\right)},n=0,1,\dots,

are called Euler splines of degree n. For each n, S_{n}(x) is the unique bounded function such that S_{n}(x)\in\mathcal{S}_{n} and

24.17.4 S_{n}(k)=(-1)^{k},k\in\mathbb{Z}.

The function S_{n}(x) is also optimal in a certain sense; see Schoenberg (1971).

Bernoulli Monosplines

A function of the form x^{n}-S(x), with S(x)\in\mathcal{S}_{n-1} is called a cardinal monospline of degree n. Again with the notation of §24.2(iii) define

M_{n}(x) is a monospline of degree n, and it follows from (24.4.25) and (24.4.27) that

24.17.6 M_{n}(k)=0,k\in\mathbb{Z}.

For each n=1,2,\dots the function M_{n}(x) is also the unique cardinal monospline of degree n satisfying (24.17.6), provided that

24.17.7 M_{n}(x)=O\left(|x|^{\gamma}\right),x\to\pm\infty,

for some positive constant \gamma.

For any n\geq 2 the function

is the unique cardinal monospline of degree n having the least supremum norm \|F\|_{\infty} on \mathbb{R} (minimality property).

§24.17(iii) Number Theory

Bernoulli and Euler numbers and polynomials occur in: number theory via (24.4.7), (24.4.8), and other identities involving sums of powers; the Riemann zeta function and L-series (§25.15, Apostol (1976), and Ireland and Rosen (1990)); arithmetic of cyclotomic fields and the classical theory of Fermat’s last theorem (Ribenboim (1979) and Washington (1997)); p-adic analysis (Koblitz (1984, Chapter 2)).