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Subfactorial




Mathematica Notation

Traditional Notation









Gamma, Beta, Erf > Subfactorial[n] > Specific values > Specialized values





http://functions.wolfram.com/06.42.03.0006.01









  


  








Input Form





Subfactorial[n] == ((-1)^n (I Pi + ExpIntegralEi[1]))/(E (-n - 1)!) + Sum[(-1)^k/Pochhammer[n + 1, k - n], {k, 0, n}] - Sum[(-1)^k/Pochhammer[n + 1, k - n], {k, n + 1, -1}] /; Element[n, Integers]








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