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variants of this functions
PolyGamma






Mathematica Notation

Traditional Notation









Gamma, Beta, Erf > PolyGamma[nu,z] > Series representations > Asymptotic series expansions





http://functions.wolfram.com/06.15.06.0042.01









  


  










Input Form





PolyGamma[n, z] \[Proportional] D[(z - 1/2) Log[z] - z + Log[2 Pi]/2, {z, n + 1}] - (-1)^n Sum[((2 k + n - 1)!/((2 k)! z^(2 k + n))) BernoulliB[2 k], {k, 1, Infinity}] - Floor[Abs[Arg[z]]/Pi] ((-I) Pi)^(n + 1) 2^n (I Cot[Pi z] - 1) Sum[((-1)^k k! StirlingS2[n, k] (I Cot[Pi z] + 1)^k)/2^k, {k, 0, n}] /; Element[n, Integers] && n >= -1 && !(Element[z, Integers] && z < 0) && (Abs[z] -> Infinity)










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