HarmonicNumber[z] \[Proportional] HarmonicNumber[Subscript[z, 0]] + (Pi^2/6 - HarmonicNumber[Subscript[z, 0], 2]) (z - Subscript[z, 0]) + (HarmonicNumber[Subscript[z, 0], 3] - Zeta[3]) (z - Subscript[z, 0])^2 + \[Ellipsis] /; (z -> Subscript[z, 0]) && !(Element[Subscript[z, 0], Integers] && Subscript[z, 0] < 0)

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2007-05-02