Quadratic transformations and Guillera’s formulas for 1/π2

We prove two new series of Ramanujan type for 1/π².     

On theorems of Gelfond and Selberg concerning integral-valued entire functions

For each sN define the constant θ_s with the following properties: if an entire function g(z) of type t(g)<θ_s satisfies then g is a polynomial; conversely, for any δ>0 there exists an entire transcendental function g(z) satisfying the display conditin and t(g)<θ_s+δ. The result θ₁=log2 is known due to Hardy and Pólya. We provide the upper bound θ_sπs/3 and improve earlier lower bounds due to Gelfond (1929) and Selberg (1941).     

One of the Eight Numbers ζ(5),ζ(7),...,ζ(17),ζ(19) Is Irrational

Mathematical Notes -     

A refinement of Nesterenko’s linear independence criterion with applications to zeta values

We refine (and give a new proof of) Nesterenko’s famous linear independence criterion from 1985, by making use of the fact that some coefficients of linear forms may have large common divisors. This is a typical situation appearing in the context of hypergeometric constructions of \mathbbQ{\mathbb{Q}}-linear forms involving zeta values or their q-analogs. We apply our criterion to sharpen previously known results in this direction.     

Complex series for 1/π

Many series for 1/?? were discovered since the appearance of S. Ramanujan??s famous paper ??Modular equations and approximation to ???? published in 1914. Almost all these series involve only real numbers. Recently, in an attempt to prove a series for 1/?? discovered by Z.-W.?Sun, the authors found that a series for 1/?? involving complex numbers is needed. In this article, we illustrate a method that would allow us to prove series of this type.     

Ramanujan-type supercongruences

We present several supercongruences that may be viewed as p-adic analogues of Ramanujan-type series for 1/π and 1/π², and prove three of these examples.     

Euler’s constant, q-logarithms, and formulas of Ramanujan and Gosper

The aim of the paper is to relate computational and arithmetic questions about Euler’s constant γ with properties of the values of the q-logarithm function, with natural choice of~q. By these means, we generalize a classical formula for γ due to Ramanujan, together with Vacca’s and Gosper’s series for γ, as well as deduce irrationality criteria and tests and new asymptotic formulas for computing Euler’s constant. The main tools are Euler-type integrals and hypergeometric series. 2000 Mathematics Subject Classification Primary—11Y60; Secondary—11J72, 33C20, 33D15 The work of the second author is supported by an Alexander von Humboldt research fellowship Dedication: To Leonhard Euler on his 300th birthday.     

Approximations to -, di- and tri-logarithms

We propose hypergeometric constructions of simultaneous approximations to polylogarithms. These approximations suit for computing the values of polylogarithms and satisfy 4-term Apéry-like (polynomial) recursions.