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ArcSech






Mathematica Notation

Traditional Notation









Elementary Functions > ArcSech[z] > Series representations > Generalized power series > Expansions on branch cuts > For the function itself > In the left half-plane near the origin





http://functions.wolfram.com/01.30.06.0048.01









  


  










Input Form





ArcSech[z] == 2 Pi Floor[Arg[x - z]/(2 Pi)] Exp[(-((Pi I)/2)) Floor[Arg[x - z]/(2 Pi)]] + (Pi I)/2 - I Sum[(-1)^k x^(-1 - k) HypergeometricPFQ[{1/2, (1 + k)/2, 1 + k/2}, {1, 3/2}, 1/x^2] (z - x)^k, {k, 0, Infinity}] /; Element[x, Reals] && -1 < x < 0










Standard Form





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MathML Form







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Rule Form





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Date Added to functions.wolfram.com (modification date)





2007-05-02