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arXiv · 1909.02700

An algorithm of computing special values of Dwork's p-adic hypergeometric functions in polynomial time

Masanori Asakura
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Abstract

Dwork's $p$-adic hypergeometric function is defined to be a ratio ${}_sF_{s-1}(t)/{}_sF_{s-1}(t^p)$ of hypergeometric power series. Dwork showed that it is a uniform limit of rational functions, and hence one can define special values on $|t|_p=1$. However to compute the value modulo $p^n$ in the naive method, the bit complexity increases by exponential when $n\to\infty$. In this paper we present a certain algorithm whose complexity increases at most $O(n^4(\log n)^3)$.

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Masanori Asakura. 2019-09-06. An algorithm of computing special values of Dwork's p-adic hypergeometric functions in polynomial time. https://arxiv.org/abs/1909.02700

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