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24 Bernoulli and Euler PolynomialsComputation

§24.19 Methods of Computation

Contents
  1. §24.19(i) Bernoulli and Euler Numbers and Polynomials
  2. §24.19(ii) Values of B_{n} Modulo p

§24.19(i) Bernoulli and Euler Numbers and Polynomials

Equations (24.5.3) and (24.5.4) enable B_{n} and E_{n} to be computed by recurrence. For higher values of n more efficient methods are available. For example, the tangent numbers T_{n} can be generated by simple recurrence relations obtained from (24.15.3), then (24.15.4) is applied. A similar method can be used for the Euler numbers based on (4.19.5). For details see Knuth and Buckholtz (1967).

Another method is based on the identities

24.19.2
D_{2n}=\prod_{p-1\mathbin{|}2n}p,
B_{2n}=\dfrac{N_{2n}}{D_{2n}}.

If \widetilde{N}_{2n} denotes the right-hand side of (24.19.1) but with the second product taken only for p\leq\left\lfloor(\pi e)^{-1}2n\right\rfloor+1, then N_{2n}=\left\lceil\widetilde{N}_{2n}\right\rceil for n\geq 2. For proofs and further information see Fillebrown (1992).

For other information see Chellali (1988) and Zhang and Jin (1996, pp. 1–11). For algorithms for computing B_{n}, E_{n}, B_{n}\left(x\right), and E_{n}\left(x\right) see Spanier and Oldham (1987, pp. 37, 41, 171, and 179–180).

§24.19(ii) Values of B_{n} Modulo p

For number-theoretic applications it is important to compute B_{2n}\pmod{p} for 2n\leq p-3; in particular to find the irregular pairs (2n,p) for which B_{2n}\equiv 0\pmod{p}. We list here three methods, arranged in increasing order of efficiency.