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arXiv · 1906.08347

Logarithmic integrals, zeta values, and tiered binomial coefficients

Michael E. Hoffman·Markus Kuba
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Abstract

We study logarithmic integrals of the form $\int_0^1 x^i\ln^n(x)\ln^m(1-x)dx$. They are expressed as a rational linear combination of certain rational numbers $(n,m)_i$, which we call tiered binomial coefficients, and products of the zeta values $\zeta(2)$, $\zeta(3)$,\dots. Various properties of the tiered binomial coefficients are established. They involve, amongst others, the binomial transform, truncated multiple zeta and multiple zeta star values, as well as special functions. As an application we discuss the limit law of the number of comparisons of the Quicksort algorithm: we reprove that the moments of the limit law are rational polynomials in the zeta values. A novel expression for the cumulants of the Quicksort limit is also presented.

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Michael E. Hoffman, Markus Kuba. 2019-06-19. Logarithmic integrals, zeta values, and tiered binomial coefficients. https://arxiv.org/abs/1906.08347

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