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 | | http://functions.wolfram.com/09.50.02.0001.01 | 
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 | | KleinInvariantJ[z] == (EllipticTheta[2, 0, E^(Pi I z)]^8 + 
     EllipticTheta[3, 0, E^(Pi I z)]^8 + EllipticTheta[4, 0, E^(Pi I z)]^8)^3/
   (54 (EllipticTheta[2, 0, E^(Pi I z)] EllipticTheta[3, 0, E^(Pi I z)] 
      EllipticTheta[4, 0, E^(Pi I z)])^8) /; Im[z] > 0 | 
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   <math xmlns='http://www.w3.org/1998/Math/MathML' mathematica:form='TraditionalForm' xmlns:mathematica='http://www.wolfram.com/XML/'>  <semantics>  <mrow>  <mrow>  <semantics>  <mrow>  <mi> J </mi>  <mo> ⁡ </mo>  <mo> ( </mo>  <mi> z </mi>  <mo> ) </mo>  </mrow>  <annotation encoding='Mathematica'> TagBox[RowBox[List["J", "(", TagBox["z", Rule[Editable, True]], ")"]], InterpretTemplate[Function[KleinInvariantJ[Slot[1]]]]] </annotation>  </semantics>  <mo> ⩵ </mo>  <mfrac>  <msup>  <mrow>  <mo> ( </mo>  <mrow>  <msup>  <mrow>  <msub>  <mi> ϑ </mi>  <mn> 2 </mn>  </msub>  <mo> ( </mo>  <mrow>  <mn> 0 </mn>  <mo> , </mo>  <msup>  <mi> ⅇ </mi>  <mrow>  <mi> π </mi>  <mo> ⁢ </mo>  <mi> ⅈ </mi>  <mo> ⁢ </mo>  <mi> z </mi>  </mrow>  </msup>  </mrow>  <mo> ) </mo>  </mrow>  <mn> 8 </mn>  </msup>  <mo> + </mo>  <msup>  <mrow>  <msub>  <mi> ϑ </mi>  <mn> 3 </mn>  </msub>  <mo> ( </mo>  <mrow>  <mn> 0 </mn>  <mo> , </mo>  <msup>  <mi> ⅇ </mi>  <mrow>  <mi> π </mi>  <mo> ⁢ </mo>  <mi> ⅈ </mi>  <mo> ⁢ </mo>  <mi> z </mi>  </mrow>  </msup>  </mrow>  <mo> ) </mo>  </mrow>  <mn> 8 </mn>  </msup>  <mo> + </mo>  <msup>  <mrow>  <msub>  <mi> ϑ </mi>  <mn> 4 </mn>  </msub>  <mo> ( </mo>  <mrow>  <mn> 0 </mn>  <mo> , </mo>  <msup>  <mi> ⅇ </mi>  <mrow>  <mi> π </mi>  <mo> ⁢ </mo>  <mi> ⅈ </mi>  <mo> ⁢ </mo>  <mi> z </mi>  </mrow>  </msup>  </mrow>  <mo> ) </mo>  </mrow>  <mn> 8 </mn>  </msup>  </mrow>  <mo> ) </mo>  </mrow>  <mn> 3 </mn>  </msup>  <mrow>  <mn> 54 </mn>  <mo> ⁢ </mo>  <msup>  <mrow>  <mo> ( </mo>  <mrow>  <mrow>  <msub>  <mi> ϑ </mi>  <mn> 2 </mn>  </msub>  <mo> ( </mo>  <mrow>  <mn> 0 </mn>  <mo> , </mo>  <msup>  <mi> ⅇ </mi>  <mrow>  <mi> π </mi>  <mo> ⁢ </mo>  <mi> ⅈ </mi>  <mo> ⁢ </mo>  <mi> z </mi>  </mrow>  </msup>  </mrow>  <mo> ) </mo>  </mrow>  <mo> ⁢ </mo>  <mrow>  <msub>  <mi> ϑ </mi>  <mn> 3 </mn>  </msub>  <mo> ( </mo>  <mrow>  <mn> 0 </mn>  <mo> , </mo>  <msup>  <mi> ⅇ </mi>  <mrow>  <mi> π </mi>  <mo> ⁢ </mo>  <mi> ⅈ </mi>  <mo> ⁢ </mo>  <mi> z </mi>  </mrow>  </msup>  </mrow>  <mo> ) </mo>  </mrow>  <mo> ⁢ </mo>  <mrow>  <msub>  <mi> ϑ </mi>  <mn> 4 </mn>  </msub>  <mo> ( </mo>  <mrow>  <mn> 0 </mn>  <mo> , </mo>  <msup>  <mi> ⅇ </mi>  <mrow>  <mi> π </mi>  <mo> ⁢ </mo>  <mi> ⅈ </mi>  <mo> ⁢ </mo>  <mi> z </mi>  </mrow>  </msup>  </mrow>  <mo> ) </mo>  </mrow>  </mrow>  <mo> ) </mo>  </mrow>  <mn> 8 </mn>  </msup>  </mrow>  </mfrac>  </mrow>  <mo> /; </mo>  <mrow>  <mrow>  <mi> Im </mi>  <mo> ⁡ </mo>  <mo> ( </mo>  <mi> z </mi>  <mo> ) </mo>  </mrow>  <mo> > </mo>  <mn> 0 </mn>  </mrow>  </mrow>  <annotation-xml encoding='MathML-Content'>  <apply>  <ci> Condition </ci>  <apply>  <eq />  <apply>  <ci> KleinInvariantJ </ci>  <ci> z </ci>  </apply>  <apply>  <times />  <apply>  <power />  <apply>  <plus />  <apply>  <power />  <apply>  <ci> EllipticTheta </ci>  <cn type='integer'> 2 </cn>  <cn type='integer'> 0 </cn>  <apply>  <power />  <exponentiale />  <apply>  <times />  <pi />  <imaginaryi />  <ci> z </ci>  </apply>  </apply>  </apply>  <cn type='integer'> 8 </cn>  </apply>  <apply>  <power />  <apply>  <ci> EllipticTheta </ci>  <cn type='integer'> 3 </cn>  <cn type='integer'> 0 </cn>  <apply>  <power />  <exponentiale />  <apply>  <times />  <pi />  <imaginaryi />  <ci> z </ci>  </apply>  </apply>  </apply>  <cn type='integer'> 8 </cn>  </apply>  <apply>  <power />  <apply>  <ci> EllipticTheta </ci>  <cn type='integer'> 4 </cn>  <cn type='integer'> 0 </cn>  <apply>  <power />  <exponentiale />  <apply>  <times />  <pi />  <imaginaryi />  <ci> z </ci>  </apply>  </apply>  </apply>  <cn type='integer'> 8 </cn>  </apply>  </apply>  <cn type='integer'> 3 </cn>  </apply>  <apply>  <power />  <apply>  <times />  <cn type='integer'> 54 </cn>  <apply>  <power />  <apply>  <times />  <apply>  <ci> EllipticTheta </ci>  <cn type='integer'> 2 </cn>  <cn type='integer'> 0 </cn>  <apply>  <power />  <exponentiale />  <apply>  <times />  <pi />  <imaginaryi />  <ci> z </ci>  </apply>  </apply>  </apply>  <apply>  <ci> EllipticTheta </ci>  <cn type='integer'> 3 </cn>  <cn type='integer'> 0 </cn>  <apply>  <power />  <exponentiale />  <apply>  <times />  <pi />  <imaginaryi />  <ci> z </ci>  </apply>  </apply>  </apply>  <apply>  <ci> EllipticTheta </ci>  <cn type='integer'> 4 </cn>  <cn type='integer'> 0 </cn>  <apply>  <power />  <exponentiale />  <apply>  <times />  <pi />  <imaginaryi />  <ci> z </ci>  </apply>  </apply>  </apply>  </apply>  <cn type='integer'> 8 </cn>  </apply>  </apply>  <cn type='integer'> -1 </cn>  </apply>  </apply>  </apply>  <apply>  <gt />  <apply>  <imaginary />  <ci> z </ci>  </apply>  <cn type='integer'> 0 </cn>  </apply>  </apply>  </annotation-xml>  </semantics>  </math> 
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 | | Cell[BoxData[RowBox[List[RowBox[List["HoldPattern", "[", RowBox[List["KleinInvariantJ", "[", "z_", "]"]], "]"]], "\[RuleDelayed]", RowBox[List[FractionBox[SuperscriptBox[RowBox[List["(", RowBox[List[SuperscriptBox[RowBox[List["EllipticTheta", "[", RowBox[List["2", ",", "0", ",", SuperscriptBox["\[ExponentialE]", RowBox[List["\[Pi]", " ", "\[ImaginaryI]", " ", "z"]]]]], "]"]], "8"], "+", SuperscriptBox[RowBox[List["EllipticTheta", "[", RowBox[List["3", ",", "0", ",", SuperscriptBox["\[ExponentialE]", RowBox[List["\[Pi]", " ", "\[ImaginaryI]", " ", "z"]]]]], "]"]], "8"], "+", SuperscriptBox[RowBox[List["EllipticTheta", "[", RowBox[List["4", ",", "0", ",", SuperscriptBox["\[ExponentialE]", RowBox[List["\[Pi]", " ", "\[ImaginaryI]", " ", "z"]]]]], "]"]], "8"]]], ")"]], "3"], RowBox[List["54", " ", SuperscriptBox[RowBox[List["(", RowBox[List[RowBox[List["EllipticTheta", "[", RowBox[List["2", ",", "0", ",", SuperscriptBox["\[ExponentialE]", RowBox[List["\[Pi]", " ", "\[ImaginaryI]", " ", "z"]]]]], "]"]], " ", RowBox[List["EllipticTheta", "[", RowBox[List["3", ",", "0", ",", SuperscriptBox["\[ExponentialE]", RowBox[List["\[Pi]", " ", "\[ImaginaryI]", " ", "z"]]]]], "]"]], " ", RowBox[List["EllipticTheta", "[", RowBox[List["4", ",", "0", ",", SuperscriptBox["\[ExponentialE]", RowBox[List["\[Pi]", " ", "\[ImaginaryI]", " ", "z"]]]]], "]"]]]], ")"]], "8"]]]], "/;", RowBox[List[RowBox[List["Im", "[", "z", "]"]], ">", "0"]]]]]]]] | 
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 | | Date Added to functions.wolfram.com (modification date) | 
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