WhittakerM[\[Nu], \[Mu], z] == z^(\[Mu] + 1/2) Sum[((-(1/2))^k/k!) Hypergeometric2F1[-k, 1/2 + \[Mu] - \[Nu], 1 + 2 \[Mu], 2] z^k, {k, 0, Infinity}]

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2007-05-02