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arXiv · 2302.01900

Some Refinements of Formulae Involving Floor and Ceiling Functions

Luka Podrug·Dragutin Svrtan
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Abstract

The floor and ceiling functions appear often in mathematics and manipulating sums involving floors and ceilings is a subtle game. Fortunately, the well-known textbook Concrete Mathematics provides a nice introduction with a number of techniques explained and a number of single or double sums treated as exercises. For two such double sums we provide their single-sum analogues. These closed-form identities are given in terms of a dual partition of the multiset (regarded as a partition) of all b-ary digits of a nonnegative integer. We also present the double- and single-sum analogues involving the fractional part function and the shifted fractional part function.

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Luka Podrug, Dragutin Svrtan. 2023-02-03. Some Refinements of Formulae Involving Floor and Ceiling Functions. https://arxiv.org/abs/2302.01900

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