Underapproximation by Egyptian fractions

نویسندگان

چکیده

An increasing sequence $(x_i)_{i=1}^n$ of positive integers is an $n$-term Egyptian underapproximation $\theta \in (0,1]$ if $\sum_{i=1}^n \frac{1}{x_i} < \theta$. A greedy algorithm constructs $\theta$. For some but not all numbers $\theta$, the gives a unique best for $n$. infinite set rational constructed which underapproximations are best, and also studied.

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ژورنال

عنوان ژورنال: Journal of Number Theory

سال: 2023

ISSN: ['0022-314X', '1096-1658']

DOI: https://doi.org/10.1016/j.jnt.2022.07.005