InverseJacobiSN[z, m] == Sum[(Pochhammer[1/2, k]^2/k!^2) (ArcSin[z] - (Sqrt[1 - z^2]/(2 z)) Sum[((j - 1)!/Pochhammer[1/2, j]) z^(2 j), {j, 1, k}]) m^k, {k, 0, Infinity}] /; Abs[m] < 1

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2007-05-02