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arXiv · 0911.3110

Faster exponentials of power series

David Harvey
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Abstract

We describe a new algorithm for computing exp(f) where f is a power series in C[[x]]. If M(n) denotes the cost of multiplying polynomials of degree n, the new algorithm costs (2.1666... + o(1)) M(n) to compute exp(f) to order n. This improves on the previous best result, namely (2.333... + o(1)) M(n).

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David Harvey. 2009-11-16. Faster exponentials of power series. https://arxiv.org/abs/0911.3110

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