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arXiv · 2303.17962

An exact series expansion for the Dottie number

Jean-Christophe Pain
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Abstract

In this article, an exact series expansion for the Dottie number (solution of the equation $\cos(x) = x$) is presented. Its derivation consists in combining the Kaplan representation of the Dottie number as a series in odd powers of $\pi$, with a series for $\pi^{2k+1}$ ($k\geq 1$) obtained using the Fa\`a di Bruno formula.

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Jean-Christophe Pain. 2023-03-31. An exact series expansion for the Dottie number. https://arxiv.org/abs/2303.17962

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