Three essays on Machin's type formulas

Fuente: arXiv
Salvato in:
Dettagli Bibliografici
Autori principali: Gasull, Armengol, Luca, Florian, Varona, Juan L.
Natura: Preprint
Pubblicazione: 2023
Soggetti:
Accesso online:
Tags: Aggiungi Tag
Nessun Tag, puoi essere il primo ad aggiungerne!!
_version_ 1866915087940321280
author Gasull, Armengol
Luca, Florian
Varona, Juan L.
author_facet Gasull, Armengol
Luca, Florian
Varona, Juan L.
contents We study three questions related to Machin's type formulas. The first one gives all two terms Machin formulas where both arctangent functions are evaluated $2$-integers, that is values of the form $b/2^a$ for some integers $a$ and~$b$. These formulas are computationally useful because multiplication or division by a power of two is a very fast operation for most computers. The second one presents a method for finding infinitely many formulas with $N$ terms. In the particular case $N=2$ the method is quite useful. It recovers most known formulas, gives some new ones, and allows to prove in an easy way that there are two terms Machin formulas with Lehmer measure as small as desired. Finally, we correct an oversight from previous result and give all Machin's type formulas with two terms involving arctangents of powers of the golden section.
format Preprint
id arxiv_https___arxiv_org_abs_2302_00154
institution arXiv
publishDate 2023
record_format arxiv
spellingShingle Three essays on Machin's type formulas
Gasull, Armengol
Luca, Florian
Varona, Juan L.
Number Theory
11Y60 (Primary), 11D45, 33B10 (Secondary)
We study three questions related to Machin's type formulas. The first one gives all two terms Machin formulas where both arctangent functions are evaluated $2$-integers, that is values of the form $b/2^a$ for some integers $a$ and~$b$. These formulas are computationally useful because multiplication or division by a power of two is a very fast operation for most computers. The second one presents a method for finding infinitely many formulas with $N$ terms. In the particular case $N=2$ the method is quite useful. It recovers most known formulas, gives some new ones, and allows to prove in an easy way that there are two terms Machin formulas with Lehmer measure as small as desired. Finally, we correct an oversight from previous result and give all Machin's type formulas with two terms involving arctangents of powers of the golden section.
title Three essays on Machin's type formulas
topic Number Theory
11Y60 (Primary), 11D45, 33B10 (Secondary)
url https://arxiv.org/abs/2302.00154