A novel algorithm for nested summation and hypergeometric expansions

  title={A novel algorithm for nested summation and hypergeometric expansions},
  author={Andrew J. McLeod and Henrik J. Munch and Georgios Papathanasiou and Matt von Hippel},
  journal={Journal of High Energy Physics},
Abstract We consider a class of sums over products of Z-sums whose arguments differ by a symbolic integer. Such sums appear, for instance, in the expansion of Gauss hypergeometric functions around integer indices that depend on a symbolic parameter. We present a telescopic algorithm for efficiently converting these sums into generalized polylogarithms, Z-sums, and cyclotomic harmonic sums for generic values of this parameter. This algorithm is illustrated by computing the double pentaladder… Expand

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