Smallest common denominators for the homogeneous components of the Baker-Campbell-Hausdorff series

Harald Hofstätter

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arXiv · 2012.03818

Smallest common denominators for the homogeneous components of the Baker-Campbell-Hausdorff series

Harald Hofstätter

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Abstract

In a recent paper the author derived a formula for calculating common denominators for the homogeneous components of the Baker-Campbell-Hausdorff (BCH) series. In the present work it is proved that this formula actually yields the smallest such common denominators. In an appendix a new efficient algorithm for computing coefficients of the BCH series is presented, which is based on these common denominators, and requires only integer arithmetic rather than less efficient rational arithmetic.

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Harald Hofstätter. 2020-12-07. Smallest common denominators for the homogeneous components of the Baker-Campbell-Hausdorff series. https://arxiv.org/abs/2012.03818

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