ChebyshevT[\[Nu], z] == 1/2/(z^\[Nu] (1 + (Sqrt[z^2] Sqrt[-1 + z^2])/z^2)^\[Nu]) + (1/2) z^\[Nu] (1 + (Sqrt[z^2] Sqrt[-1 + z^2])/z^2)^\[Nu] /; !IntervalMemberQ[Interval[{-1, 0}], z] && !Element[\[Nu], Integers]

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2007-05-02