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 | | http://functions.wolfram.com/13.05.29.0002.01 | 
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 | | DivisorSigma[k, n] >= EulerPhi[n]^k + DivisorSigma[0, n]^2 /; k >= 2 && n >= 3 | 
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 | | Cell[BoxData[RowBox[List[RowBox[List[RowBox[List["DivisorSigma", "[", RowBox[List["k", ",", "n"]], "]"]], "\[GreaterEqual]", RowBox[List[SuperscriptBox[RowBox[List["EulerPhi", "[", "n", "]"]], "k"], "+", SuperscriptBox[RowBox[List["DivisorSigma", "[", RowBox[List["0", ",", "n"]], "]"]], "2"]]]]], "/;", RowBox[List[RowBox[List["k", "\[GreaterEqual]", "2"]], "\[And]", RowBox[List["n", "\[GreaterEqual]", "3"]]]]]]]] | 
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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>  <mrow>  <msub>  <semantics>  <mi> σ </mi>  <annotation encoding='Mathematica'> TagBox["\[Sigma]", DivisorSigma] </annotation>  </semantics>  <mi> k </mi>  </msub>  <mo> ( </mo>  <mi> n </mi>  <mo> ) </mo>  </mrow>  <mo> ≥ </mo>  <mrow>  <msup>  <mrow>  <semantics>  <mi> ϕ </mi>  <annotation encoding='Mathematica'> TagBox["\[Phi]", EulerPhi] </annotation>  </semantics>  <mo> ( </mo>  <mi> n </mi>  <mo> ) </mo>  </mrow>  <mi> k </mi>  </msup>  <mo> + </mo>  <msup>  <mrow>  <msub>  <semantics>  <mi> σ </mi>  <annotation encoding='Mathematica'> TagBox["\[Sigma]", DivisorSigma] </annotation>  </semantics>  <mn> 0 </mn>  </msub>  <mo> ( </mo>  <mi> n </mi>  <mo> ) </mo>  </mrow>  <mn> 2 </mn>  </msup>  </mrow>  </mrow>  <mo> /; </mo>  <mrow>  <mrow>  <mi> k </mi>  <mo> ≥ </mo>  <mn> 2 </mn>  </mrow>  <mo> ∧ </mo>  <mrow>  <mi> n </mi>  <mo> ≥ </mo>  <mn> 3 </mn>  </mrow>  </mrow>  </mrow>  <annotation-xml encoding='MathML-Content'>  <apply>  <ci> Condition </ci>  <apply>  <geq />  <apply>  <ci> DivisorSigma </ci>  <ci> k </ci>  <ci> n </ci>  </apply>  <apply>  <plus />  <apply>  <power />  <apply>  <ci> EulerPhi </ci>  <ci> n </ci>  </apply>  <ci> k </ci>  </apply>  <apply>  <power />  <apply>  <ci> DivisorSigma </ci>  <cn type='integer'> 0 </cn>  <ci> n </ci>  </apply>  <cn type='integer'> 2 </cn>  </apply>  </apply>  </apply>  <apply>  <and />  <apply>  <geq />  <ci> k </ci>  <cn type='integer'> 2 </cn>  </apply>  <apply>  <geq />  <ci> n </ci>  <cn type='integer'> 3 </cn>  </apply>  </apply>  </apply>  </annotation-xml>  </semantics>  </math> 
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 | | Cell[BoxData[RowBox[List[RowBox[List[RowBox[List["DivisorSigma", "[", RowBox[List["k", ",", "n"]], "]"]], "\[GreaterEqual]", RowBox[List[SuperscriptBox[RowBox[List["EulerPhi", "[", "n", "]"]], "k"], "+", SuperscriptBox[RowBox[List["DivisorSigma", "[", RowBox[List["0", ",", "n"]], "]"]], "2"]]]]], "/;", RowBox[List[RowBox[List["k", "\[GreaterEqual]", "2"]], "&&", RowBox[List["n", "\[GreaterEqual]", "3"]]]]]]]] | 
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 | | Date Added to functions.wolfram.com (modification date) | 
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