Hurwitz Zeta Function - Rational Values

Rational Values

The Hurwitz zeta function occurs in a number of striking identities at rational values. In particular, values in terms of the Euler polynomials :

E_{2n-1}\left(\frac{p}{q}\right) =
(-1)^n \frac{4(2n-1)!}{(2\pi q)^{2n}}
\sum_{k=1}^q \zeta\left(2n,\frac{2k-1}{2q}\right)
\cos \frac{(2k-1)\pi p}{q}

and

E_{2n}\left(\frac{p}{q}\right) =
(-1)^n \frac{4(2n)!}{(2\pi q)^{2n+1}}
\sum_{k=1}^q \zeta\left(2n+1,\frac{2k-1}{2q}\right)
\sin \frac{(2k-1)\pi p}{q}

One also has

\zeta\left(s,\frac{2p-1}{2q}\right) =
2(2q)^{s-1} \sum_{k=1}^q \left[
C_s\left(\frac{k}{q}\right) \cos \left(\frac{(2p-1)\pi k}{q}\right) +
S_s\left(\frac{k}{q}\right) \sin \left(\frac{(2p-1)\pi k}{q}\right)
\right]

which holds for . Here, the and are defined by means of the Legendre chi function as

and

For integer values of ν, these may be expressed in terms of the Euler polynomials. These relations may be derived by employing the functional equation together with Hurwitz's formula, given above.

Read more about this topic:  Hurwitz Zeta Function

Famous quotes containing the words rational and/or values:

    To a first approximation, the intentional strategy consists of treating the object whose behavior you want to predict as a rational agent with beliefs and desires and other mental states exhibiting what Brentano and others call intentionality.
    Daniel Clement Dennett (b. 1942)

    ... the loss of belief in future states is politically, though certainly not spiritually, the most significant distinction between our present period and the centuries before. And this loss is definite. For no matter how religious our world may turn again, or how much authentic faith still exists in it, or how deeply our moral values may be rooted in our religious systems, the fear of hell is no longer among the motives which would prevent or stimulate the actions of a majority.
    Hannah Arendt (1906–1975)