|  | 
 |  
 |  
 |  
 |  
 |  
 |  |  
 |  
 
 |  
 |  
 |  
 |  
 |  
 |  |  
 |  
 
 |  
 |  
 |  
 |  
 |  
 |  |  
 |  
 
 |  
 |  
 |  
 |  |   
 |  
 |  
 |  
 |  
 |  
 |  
 |  |  
 |  
 |  
 |  
 |  
 |  
 |  
 | | http://functions.wolfram.com/06.15.06.0012.01 | 
 |  
 |  
 |  
 |  
 |  
 |  |   
 |  
 |  |  |   
 |  
 |  
 |  
 |  
 |  
 |  
 |  |  
 |  
 |  
 |  
 |  
 |  
 |  
 | | PolyGamma[n, z] == (-1)^(n + 1) n! (z^(-1 - n) + (1 + z)^(-1 - n) + 
    (2 + z)^(-1 - n) + \[Ellipsis]) /; Element[n, Integers] && n > 0 | 
 |  
 |  
 |  
 |  
 |  
 |  |   
 |  
 |  
 |  
 |  
 |  
 |  
 |  |  
 |  
 |  
 |  
 |  
 |  
 |  
 | | Cell[BoxData[RowBox[List[RowBox[List[RowBox[List["PolyGamma", "[", RowBox[List["n", ",", "z"]], "]"]], "\[Equal]", RowBox[List[SuperscriptBox[RowBox[List["(", RowBox[List["-", "1"]], ")"]], RowBox[List["n", "+", "1"]]], " ", RowBox[List["n", "!"]], " ", RowBox[List["(", RowBox[List[SuperscriptBox["z", RowBox[List[RowBox[List["-", "1"]], "-", "n"]]], "+", SuperscriptBox[RowBox[List["(", RowBox[List["1", "+", "z"]], ")"]], RowBox[List[RowBox[List["-", "1"]], "-", "n"]]], "+", SuperscriptBox[RowBox[List["(", RowBox[List["2", "+", "z"]], ")"]], RowBox[List[RowBox[List["-", "1"]], "-", "n"]]], "+", "\[Ellipsis]"]], ")"]]]]]], "/;", RowBox[List[RowBox[List["n", "\[Element]", "Integers"]], "\[And]", RowBox[List["n", ">", "0"]]]]]]]] | 
 |  
 |  
 |  
 |  
 |  
 |  |   
 |  
 |  
 |  
 |  
 |  
 |  
 |  |  
 |  
 |  
 |  
 |  
 |  
 |  
 |  |  
 |  
 |  
 | | 
   <math xmlns='http://www.w3.org/1998/Math/MathML' mathematica:form='TraditionalForm' xmlns:mathematica='http://www.wolfram.com/XML/'>  <semantics>  <mrow>  <mrow>  <mrow>  <msup>  <semantics>  <mi> ψ </mi>  <annotation encoding='Mathematica'> TagBox["\[Psi]", PolyGamma] </annotation>  </semantics>  <mrow>  <mo> ( </mo>  <mi> n </mi>  <mo> ) </mo>  </mrow>  </msup>  <mo> ( </mo>  <mi> z </mi>  <mo> ) </mo>  </mrow>  <mo> ⩵ </mo>  <mrow>  <msup>  <mrow>  <mo> ( </mo>  <mrow>  <mo> - </mo>  <mn> 1 </mn>  </mrow>  <mo> ) </mo>  </mrow>  <mrow>  <mi> n </mi>  <mo> + </mo>  <mn> 1 </mn>  </mrow>  </msup>  <mo> ⁢ </mo>  <mrow>  <mi> n </mi>  <mo> ! </mo>  </mrow>  <mo> ⁢ </mo>  <mrow>  <mo> ( </mo>  <mrow>  <msup>  <mi> z </mi>  <mrow>  <mrow>  <mo> - </mo>  <mi> n </mi>  </mrow>  <mo> - </mo>  <mn> 1 </mn>  </mrow>  </msup>  <mo> + </mo>  <msup>  <mrow>  <mo> ( </mo>  <mrow>  <mi> z </mi>  <mo> + </mo>  <mn> 1 </mn>  </mrow>  <mo> ) </mo>  </mrow>  <mrow>  <mrow>  <mo> - </mo>  <mi> n </mi>  </mrow>  <mo> - </mo>  <mn> 1 </mn>  </mrow>  </msup>  <mo> + </mo>  <msup>  <mrow>  <mo> ( </mo>  <mrow>  <mi> z </mi>  <mo> + </mo>  <mn> 2 </mn>  </mrow>  <mo> ) </mo>  </mrow>  <mrow>  <mrow>  <mo> - </mo>  <mi> n </mi>  </mrow>  <mo> - </mo>  <mn> 1 </mn>  </mrow>  </msup>  <mo> + </mo>  <mo> … </mo>  </mrow>  <mo> ) </mo>  </mrow>  </mrow>  </mrow>  <mo> /; </mo>  <mrow>  <mi> n </mi>  <mo> ∈ </mo>  <msup>  <mi> ℕ </mi>  <mo> + </mo>  </msup>  </mrow>  </mrow>  <annotation-xml encoding='MathML-Content'>  <apply>  <ci> Condition </ci>  <apply>  <eq />  <apply>  <ci> PolyGamma </ci>  <ci> n </ci>  <ci> z </ci>  </apply>  <apply>  <times />  <apply>  <power />  <cn type='integer'> -1 </cn>  <apply>  <plus />  <ci> n </ci>  <cn type='integer'> 1 </cn>  </apply>  </apply>  <apply>  <factorial />  <ci> n </ci>  </apply>  <apply>  <plus />  <apply>  <power />  <ci> z </ci>  <apply>  <plus />  <apply>  <times />  <cn type='integer'> -1 </cn>  <ci> n </ci>  </apply>  <cn type='integer'> -1 </cn>  </apply>  </apply>  <apply>  <power />  <apply>  <plus />  <ci> z </ci>  <cn type='integer'> 1 </cn>  </apply>  <apply>  <plus />  <apply>  <times />  <cn type='integer'> -1 </cn>  <ci> n </ci>  </apply>  <cn type='integer'> -1 </cn>  </apply>  </apply>  <apply>  <power />  <apply>  <plus />  <ci> z </ci>  <cn type='integer'> 2 </cn>  </apply>  <apply>  <plus />  <apply>  <times />  <cn type='integer'> -1 </cn>  <ci> n </ci>  </apply>  <cn type='integer'> -1 </cn>  </apply>  </apply>  <ci> … </ci>  </apply>  </apply>  </apply>  <apply>  <in />  <ci> n </ci>  <apply>  <ci> SuperPlus </ci>  <ci> ℕ </ci>  </apply>  </apply>  </apply>  </annotation-xml>  </semantics>  </math> 
   | 
 |  
 |  
 |  
 |  
 |  
 |  |  
 |  |  
 |  
 |  
 |  |  
 |  |  
 |  |  
 |  
 |  
 |  |  
 | | Cell[BoxData[RowBox[List[RowBox[List["HoldPattern", "[", RowBox[List["PolyGamma", "[", RowBox[List["n_", ",", "z_"]], "]"]], "]"]], "\[RuleDelayed]", RowBox[List[RowBox[List[SuperscriptBox[RowBox[List["(", RowBox[List["-", "1"]], ")"]], RowBox[List["n", "+", "1"]]], " ", RowBox[List["n", "!"]], " ", RowBox[List["(", RowBox[List[SuperscriptBox["z", RowBox[List[RowBox[List["-", "1"]], "-", "n"]]], "+", SuperscriptBox[RowBox[List["(", RowBox[List["1", "+", "z"]], ")"]], RowBox[List[RowBox[List["-", "1"]], "-", "n"]]], "+", SuperscriptBox[RowBox[List["(", RowBox[List["2", "+", "z"]], ")"]], RowBox[List[RowBox[List["-", "1"]], "-", "n"]]], "+", "\[Ellipsis]"]], ")"]]]], "/;", RowBox[List[RowBox[List["n", "\[Element]", "Integers"]], "&&", RowBox[List["n", ">", "0"]]]]]]]]]] | 
 |  
 |   
 |  
 |  
 | |   
 |  
 |  
 |  
 |  
 |  
 |  
 | | Date Added to functions.wolfram.com (modification date) | 
 |  
 |  
 |  
 |  
 |  
 |  
 |  
 |  |  
 |   
 |  
 |  
 |  |  |