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arXiv · 2502.17008

Expression of special stretched $9j$ coefficients in terms of $_5F_4$ hypergeometric series

Jean-Christophe Pain
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Abstract

The Clebsch-Gordan coefficients or Wigner $3j$ symbols are known to be proportional to a $_3F_2(1)$ hypergeometric series, and Racah $6j$ coefficients to a $_4F_3(1)$. In general, however, non-trivial $9j$ symbols can not be expressed as a $_5F_4$. In this letter, we show, using the Dougall-Ramanujan identity, that special stretched $9j$ symbols can be reformulated as $_5F_4(1)$ hypergeometric series.

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Jean-Christophe Pain. 2025-02-24. Expression of special stretched $9j$ coefficients in terms of $_5F_4$ hypergeometric series. https://arxiv.org/abs/2502.17008

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