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arXiv · 1802.09858

A Short and Unified Proof of Kummer's Test

Tord Sjödin
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Abstract

Kummer's test from 1835 states that the positive series $\sum_{n=1}^\infty a_n$ is convergent if and only if there is a sequence $\{ B_n\}_1^\infty$ of positive numbers such that $B_n\cdot \frac{a_n }{a_{n+1}} -B_{n+1}\geq 1 ,$ for all sufficiently large $n$. We present an exact analysis and a short and unified proof of Kummer's test. The test has been applied to differential equations and studied in mathematical philosophy.

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Tord Sjödin. 2018-02-27. A Short and Unified Proof of Kummer's Test. https://arxiv.org/abs/1802.09858

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