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 | | http://functions.wolfram.com/13.05.29.0025.01 | 
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 | | Inequality[n^k Product[(1/Subscript[p, j]^k) ((Subscript[p, j]^(2 k) - 1)/
      (Subscript[p, j]^k - 1)), {j, 1, m}], LessEqual, DivisorSigma[k, n], 
  Less, n^k Product[Subscript[p, j]^k/(Subscript[p, j]^k - 1), {j, 1, m}]] /; 
 Element[k, Integers] && k >= 1 && 
  n == Product[Subscript[p, k]^Subscript[n, k], {k, 1, m}] && 
  Element[Subscript[p, k], Primes] && Element[Subscript[n, k], Integers] && 
  Subscript[n, k] > 0 && Subscript[p, k] < Subscript[p, k + 1] && 
  1 <= k <= m - 1 | 
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 | | Cell[BoxData[RowBox[List[RowBox[List[RowBox[List[SuperscriptBox["n", "k"], RowBox[List[UnderoverscriptBox["\[Product]", RowBox[List["j", "=", "1"]], "m"], RowBox[List[FractionBox["1", SubsuperscriptBox["p", "j", "k"]], FractionBox[RowBox[List[SubsuperscriptBox["p", "j", RowBox[List["2", "k"]]], "-", "1"]], RowBox[List[SubsuperscriptBox["p", "j", "k"], "-", "1"]]]]]]]]], "\[LessEqual]", RowBox[List["DivisorSigma", "[", RowBox[List["k", ",", "n"]], "]"]], "<", RowBox[List[SuperscriptBox["n", "k"], RowBox[List[UnderoverscriptBox["\[Product]", RowBox[List["j", "=", "1"]], "m"], FractionBox[SubsuperscriptBox["p", "j", "k"], RowBox[List[SubsuperscriptBox["p", "j", "k"], "-", "1"]]]]]]]]], "/;", RowBox[List[RowBox[List["k", "\[Element]", "Integers"]], "\[And]", RowBox[List["k", "\[GreaterEqual]", "1"]], "\[And]", RowBox[List["n", "\[Equal]", RowBox[List[UnderoverscriptBox["\[Product]", RowBox[List["k", "=", "1"]], "m"], SubsuperscriptBox["p", "k", SubscriptBox["n", "k"]]]]]], "\[And]", RowBox[List[SubscriptBox["p", "k"], "\[Element]", "Primes"]], "\[And]", RowBox[List[SubscriptBox["n", "k"], "\[Element]", "Integers"]], "\[And]", RowBox[List[SubscriptBox["n", "k"], ">", "0"]], "\[And]", RowBox[List[SubscriptBox["p", "k"], "<", SubscriptBox["p", RowBox[List["k", "+", "1"]]]]], "\[And]", RowBox[List["1", "\[LessEqual]", "k", "\[LessEqual]", RowBox[List["m", "-", "1"]]]]]]]]]] | 
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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>  <msup>  <mi> n </mi>  <mi> k </mi>  </msup>  <mo> ⁢ </mo>  <mrow>  <munderover>  <mo> ∏ </mo>  <mrow>  <mi> j </mi>  <mo> = </mo>  <mn> 1 </mn>  </mrow>  <mi> m </mi>  </munderover>  <mfrac>  <mrow>  <msubsup>  <mi> p </mi>  <mi> j </mi>  <mrow>  <mn> 2 </mn>  <mo> ⁢ </mo>  <mi> k </mi>  </mrow>  </msubsup>  <mo> - </mo>  <mn> 1 </mn>  </mrow>  <mrow>  <msubsup>  <mi> p </mi>  <mi> j </mi>  <mi> k </mi>  </msubsup>  <mo> ⁢ </mo>  <mrow>  <mo> ( </mo>  <mrow>  <msubsup>  <mi> p </mi>  <mi> j </mi>  <mi> k </mi>  </msubsup>  <mo> - </mo>  <mn> 1 </mn>  </mrow>  <mo> ) </mo>  </mrow>  </mrow>  </mfrac>  </mrow>  </mrow>  <mo> ≤ </mo>  <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>  <mi> n </mi>  <mi> k </mi>  </msup>  <mo> ⁢ </mo>  <mrow>  <munderover>  <mo> ∏ </mo>  <mrow>  <mi> j </mi>  <mo> = </mo>  <mn> 1 </mn>  </mrow>  <mi> m </mi>  </munderover>  <mfrac>  <msubsup>  <mi> p </mi>  <mi> j </mi>  <mi> k </mi>  </msubsup>  <mrow>  <msubsup>  <mi> p </mi>  <mi> j </mi>  <mi> k </mi>  </msubsup>  <mo> - </mo>  <mn> 1 </mn>  </mrow>  </mfrac>  </mrow>  </mrow>  </mrow>  <mo> /; </mo>  <mrow>  <mrow>  <mi> k </mi>  <mo> ∈ </mo>  <msup>  <mi> ℕ </mi>  <mo> + </mo>  </msup>  </mrow>  <mo> ∧ </mo>  <mrow>  <mi> n </mi>  <mo> ⩵ </mo>  <mrow>  <munderover>  <mo> ∏ </mo>  <mrow>  <mi> k </mi>  <mo> = </mo>  <mn> 1 </mn>  </mrow>  <mi> m </mi>  </munderover>  <msubsup>  <mi> p </mi>  <mi> k </mi>  <msub>  <mi> n </mi>  <mi> k </mi>  </msub>  </msubsup>  </mrow>  </mrow>  <mo> ∧ </mo>  <mrow>  <msub>  <mi> p </mi>  <mi> k </mi>  </msub>  <mo> ∈ </mo>  <semantics>  <mi> ℙ </mi>  <annotation encoding='Mathematica'> TagBox["\[DoubleStruckCapitalP]", Function[Primes]] </annotation>  </semantics>  </mrow>  <mo> ∧ </mo>  <mrow>  <msub>  <mi> n </mi>  <mi> k </mi>  </msub>  <mo> ∈ </mo>  <msup>  <mi> ℕ </mi>  <mo> + </mo>  </msup>  </mrow>  <mo> ∧ </mo>  <mrow>  <msub>  <mi> p </mi>  <mi> k </mi>  </msub>  <mo> < </mo>  <msub>  <mi> p </mi>  <mrow>  <mi> k </mi>  <mo> + </mo>  <mn> 1 </mn>  </mrow>  </msub>  </mrow>  <mo> ∧ </mo>  <mrow>  <mn> 1 </mn>  <mo> ≤ </mo>  <mi> k </mi>  <mo> ≤ </mo>  <mrow>  <mi> m </mi>  <mo> - </mo>  <mn> 1 </mn>  </mrow>  </mrow>  </mrow>  </mrow>  <annotation-xml encoding='MathML-Content'>  <apply>  <ci> Condition </ci>  <apply>  <ci> Inequality </ci>  <apply>  <times />  <apply>  <power />  <ci> n </ci>  <ci> k </ci>  </apply>  <apply>  <product />  <bvar>  <ci> j </ci>  </bvar>  <lowlimit>  <cn type='integer'> 1 </cn>  </lowlimit>  <uplimit>  <ci> m </ci>  </uplimit>  <apply>  <times />  <apply>  <plus />  <apply>  <power />  <apply>  <ci> Subscript </ci>  <ci> p </ci>  <ci> j </ci>  </apply>  <apply>  <times />  <cn type='integer'> 2 </cn>  <ci> k </ci>  </apply>  </apply>  <cn type='integer'> -1 </cn>  </apply>  <apply>  <power />  <apply>  <times />  <apply>  <power />  <apply>  <ci> Subscript </ci>  <ci> p </ci>  <ci> j </ci>  </apply>  <ci> k </ci>  </apply>  <apply>  <plus />  <apply>  <power />  <apply>  <ci> Subscript </ci>  <ci> p </ci>  <ci> j </ci>  </apply>  <ci> k </ci>  </apply>  <cn type='integer'> -1 </cn>  </apply>  </apply>  <cn type='integer'> -1 </cn>  </apply>  </apply>  </apply>  </apply>  <leq />  <apply>  <ci> DivisorSigma </ci>  <ci> k </ci>  <ci> n </ci>  </apply>  <lt />  <apply>  <times />  <apply>  <power />  <ci> n </ci>  <ci> k </ci>  </apply>  <apply>  <product />  <bvar>  <ci> j </ci>  </bvar>  <lowlimit>  <cn type='integer'> 1 </cn>  </lowlimit>  <uplimit>  <ci> m </ci>  </uplimit>  <apply>  <times />  <apply>  <power />  <apply>  <ci> Subscript </ci>  <ci> p </ci>  <ci> j </ci>  </apply>  <ci> k </ci>  </apply>  <apply>  <power />  <apply>  <plus />  <apply>  <power />  <apply>  <ci> Subscript </ci>  <ci> p </ci>  <ci> j </ci>  </apply>  <ci> k </ci>  </apply>  <cn type='integer'> -1 </cn>  </apply>  <cn type='integer'> -1 </cn>  </apply>  </apply>  </apply>  </apply>  </apply>  <apply>  <and />  <apply>  <in />  <ci> k </ci>  <apply>  <ci> SuperPlus </ci>  <ci> ℕ </ci>  </apply>  </apply>  <apply>  <eq />  <ci> n </ci>  <apply>  <product />  <bvar>  <ci> k </ci>  </bvar>  <lowlimit>  <cn type='integer'> 1 </cn>  </lowlimit>  <uplimit>  <ci> m </ci>  </uplimit>  <apply>  <power />  <apply>  <ci> Subscript </ci>  <ci> p </ci>  <ci> k </ci>  </apply>  <apply>  <ci> Subscript </ci>  <ci> n </ci>  <ci> k </ci>  </apply>  </apply>  </apply>  </apply>  <apply>  <in />  <apply>  <ci> Subscript </ci>  <ci> p </ci>  <ci> k </ci>  </apply>  <primes />  </apply>  <apply>  <in />  <apply>  <ci> Subscript </ci>  <ci> n </ci>  <ci> k </ci>  </apply>  <apply>  <ci> SuperPlus </ci>  <ci> ℕ </ci>  </apply>  </apply>  <apply>  <lt />  <apply>  <ci> Subscript </ci>  <ci> p </ci>  <ci> k </ci>  </apply>  <apply>  <ci> Subscript </ci>  <ci> p </ci>  <apply>  <plus />  <ci> k </ci>  <cn type='integer'> 1 </cn>  </apply>  </apply>  </apply>  <apply>  <leq />  <cn type='integer'> 1 </cn>  <ci> k </ci>  <apply>  <plus />  <ci> m </ci>  <cn type='integer'> -1 </cn>  </apply>  </apply>  </apply>  </apply>  </annotation-xml>  </semantics>  </math> 
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 | | Cell[BoxData[RowBox[List[RowBox[List[RowBox[List[SuperscriptBox["n", "k"], " ", RowBox[List[UnderoverscriptBox["\[Product]", RowBox[List["j", "=", "1"]], "m"], FractionBox[RowBox[List[SubsuperscriptBox["p", "j", RowBox[List["2", " ", "k"]]], "-", "1"]], RowBox[List[SubsuperscriptBox["p", "j", "k"], " ", RowBox[List["(", RowBox[List[SubsuperscriptBox["p", "j", "k"], "-", "1"]], ")"]]]]]]]]], "\[LessEqual]", RowBox[List["DivisorSigma", "[", RowBox[List["k", ",", "n"]], "]"]], "<", RowBox[List[SuperscriptBox["n", "k"], " ", RowBox[List[UnderoverscriptBox["\[Product]", RowBox[List["j", "=", "1"]], "m"], FractionBox[SubsuperscriptBox["p", "j", "k"], RowBox[List[SubsuperscriptBox["p", "j", "k"], "-", "1"]]]]]]]]], "/;", RowBox[List[RowBox[List["k", "\[Element]", "Integers"]], "&&", RowBox[List["k", "\[GreaterEqual]", "1"]], "&&", RowBox[List["n", "\[Equal]", RowBox[List[UnderoverscriptBox["\[Product]", RowBox[List["k", "=", "1"]], "m"], SubsuperscriptBox["p", "k", SubscriptBox["n", "k"]]]]]], "&&", RowBox[List[SubscriptBox["p", "k"], "\[Element]", "Primes"]], "&&", RowBox[List[SubscriptBox["n", "k"], "\[Element]", "Integers"]], "&&", RowBox[List[SubscriptBox["n", "k"], ">", "0"]], "&&", RowBox[List[SubscriptBox["p", "k"], "<", SubscriptBox["p", RowBox[List["k", "+", "1"]]]]], "&&", RowBox[List["1", "\[LessEqual]", "k", "\[LessEqual]", RowBox[List["m", "-", "1"]]]]]]]]]] | 
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 | | Date Added to functions.wolfram.com (modification date) | 
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