GCD[Subscript[n, 1], Subscript[n, 2]] == Product[Subscript[p, i, j]^Min[Subscript[\[Alpha], 1, j], Subscript[\[Alpha], 2, j]], {j, 1, Subscript[j, k]}] /; Element[Subscript[n, 1], Integers] && Subscript[n, 1] > 0 && Element[Subscript[n, 2], Integers] && Subscript[n, 2] > 0 && FactorInteger[Subscript[n, k]] == {{Subscript[p, k, 1], Subscript[\[Alpha], k, 1]}, \[Ellipsis], {Subscript[p, k, Subscript[j, k]], Subscript[\[Alpha], k, Subscript[j, k]]}} && Element[Subscript[p, k, j], Primes] && Element[Subscript[\[Alpha], k, j], Integers] && Subscript[\[Alpha], k, j] > 0 && 1 <= k <= 2

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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> <mi> gcd </mi> <mo> &#8289; </mo> <mo> ( </mo> <mrow> <msub> <mi> n </mi> <mn> 1 </mn> </msub> <mo> , </mo> <msub> <mi> n </mi> <mn> 2 </mn> </msub> </mrow> <mo> ) </mo> </mrow> <mo> &#10869; </mo> <mrow> <munderover> <mo> &#8719; </mo> <mrow> <mi> j </mi> <mo> = </mo> <mn> 1 </mn> </mrow> <msub> <mi> j </mi> <mi> k </mi> </msub> </munderover> <msubsup> <mi> p </mi> <mrow> <mi> i </mi> <mo> , </mo> <mi> j </mi> </mrow> <mrow> <mi> min </mi> <mo> &#8289; </mo> <mo> ( </mo> <mrow> <msub> <mi> &#945; </mi> <mrow> <mn> 1 </mn> <mo> , </mo> <mi> j </mi> </mrow> </msub> <mo> , </mo> <msub> <mi> &#945; </mi> <mrow> <mn> 2 </mn> <mo> , </mo> <mi> j </mi> </mrow> </msub> </mrow> <mo> ) </mo> </mrow> </msubsup> </mrow> </mrow> <mo> /; </mo> <mrow> <mrow> <msub> <mi> n </mi> <mn> 1 </mn> </msub> <mo> &#8712; </mo> <msup> <semantics> <mi> &#8469; </mi> <annotation encoding='Mathematica'> TagBox[&quot;\[DoubleStruckCapitalN]&quot;, Function[Integers]] </annotation> </semantics> <mo> + </mo> </msup> </mrow> <mo> &#8743; </mo> <mrow> <msub> <mi> n </mi> <mn> 2 </mn> </msub> <mo> &#8712; </mo> <msup> <semantics> <mi> &#8469; </mi> <annotation encoding='Mathematica'> TagBox[&quot;\[DoubleStruckCapitalN]&quot;, Function[Integers]] </annotation> </semantics> <mo> + </mo> </msup> </mrow> <mo> &#8743; </mo> <mrow> <mrow> <mi> factors </mi> <mo> &#8289; </mo> <mo> ( </mo> <msub> <mi> n </mi> <mi> k </mi> </msub> <mo> ) </mo> </mrow> <mo> &#10869; </mo> <mrow> <mo> { </mo> <mrow> <mrow> <mo> { </mo> <mrow> <msub> <mi> p </mi> <mrow> <mi> k </mi> <mo> , </mo> <mn> 1 </mn> </mrow> </msub> <mo> , </mo> <msub> <mi> &#945; </mi> <mrow> <mi> k </mi> <mo> , </mo> <mn> 1 </mn> </mrow> </msub> </mrow> <mo> } </mo> </mrow> <mo> , </mo> <mo> &#8230; </mo> <mo> , </mo> <mrow> <mo> { </mo> <mrow> <msub> <mi> p </mi> <mrow> <mi> k </mi> <mo> , </mo> <msub> <mi> j </mi> <mi> k </mi> </msub> </mrow> </msub> <mo> , </mo> <msub> <mi> &#945; </mi> <mrow> <mi> k </mi> <mo> , </mo> <msub> <mi> j </mi> <mi> k </mi> </msub> </mrow> </msub> </mrow> <mo> } </mo> </mrow> </mrow> <mo> } </mo> </mrow> </mrow> <mo> &#8743; </mo> <mrow> <msub> <mi> p </mi> <mrow> <mi> k </mi> <mo> , </mo> <mi> j </mi> </mrow> </msub> <mo> &#8712; </mo> <semantics> <mi> &#8473; </mi> <annotation encoding='Mathematica'> TagBox[&quot;\[DoubleStruckCapitalP]&quot;, Function[Primes]] </annotation> </semantics> </mrow> <mo> &#8743; </mo> <mrow> <msub> <mi> &#945; </mi> <mrow> <mi> k </mi> <mo> , </mo> <mi> j </mi> </mrow> </msub> <mo> &#8712; </mo> <msup> <semantics> <mi> &#8469; </mi> <annotation encoding='Mathematica'> TagBox[&quot;\[DoubleStruckCapitalN]&quot;, Function[Integers]] </annotation> </semantics> <mo> + </mo> </msup> </mrow> <mo> &#8743; </mo> <mrow> <mn> 1 </mn> <mo> &#8804; </mo> <mi> k </mi> <mo> &#8804; </mo> <mn> 2 </mn> </mrow> </mrow> </mrow> <annotation-xml encoding='MathML-Content'> <apply> <ci> Condition </ci> <apply> <eq /> <apply> <gcd /> <apply> <ci> Subscript </ci> <ci> n </ci> <cn type='integer'> 1 </cn> </apply> <apply> <ci> Subscript </ci> <ci> n </ci> <cn type='integer'> 2 </cn> </apply> </apply> <apply> <product /> <bvar> <ci> j </ci> </bvar> <lowlimit> <cn type='integer'> 1 </cn> </lowlimit> <uplimit> <apply> <ci> Subscript </ci> <ci> j </ci> <ci> k </ci> </apply> </uplimit> <apply> <power /> <apply> <ci> Subscript </ci> <ci> p </ci> <ci> i </ci> <ci> j </ci> </apply> <apply> <min /> <apply> <ci> Subscript </ci> <ci> &#945; </ci> <cn type='integer'> 1 </cn> <ci> j </ci> </apply> <apply> <ci> Subscript </ci> <ci> &#945; </ci> <cn type='integer'> 2 </cn> <ci> j </ci> </apply> </apply> </apply> </apply> </apply> <apply> <and /> <apply> <in /> <apply> <ci> Subscript </ci> <ci> n </ci> <cn type='integer'> 1 </cn> </apply> <apply> <ci> SuperPlus </ci> <integers /> </apply> </apply> <apply> <in /> <apply> <ci> Subscript </ci> <ci> n </ci> <cn type='integer'> 2 </cn> </apply> <apply> <ci> SuperPlus </ci> <integers /> </apply> </apply> <apply> <eq /> <apply> <ci> factors </ci> <apply> <ci> Subscript </ci> <ci> n </ci> <ci> k </ci> </apply> </apply> <list> <list> <apply> <ci> Subscript </ci> <ci> p </ci> <ci> k </ci> <cn type='integer'> 1 </cn> </apply> <apply> <ci> Subscript </ci> <ci> &#945; </ci> <ci> k </ci> <cn type='integer'> 1 </cn> </apply> </list> <ci> &#8230; </ci> <list> <apply> <ci> Subscript </ci> <ci> p </ci> <ci> k </ci> <apply> <ci> Subscript </ci> <ci> j </ci> <ci> k </ci> </apply> </apply> <apply> <ci> Subscript </ci> <ci> &#945; </ci> <ci> k </ci> <apply> <ci> Subscript </ci> <ci> j </ci> <ci> k </ci> </apply> </apply> </list> </list> </apply> <apply> <in /> <apply> <ci> Subscript </ci> <ci> p </ci> <ci> k </ci> <ci> j </ci> </apply> <primes /> </apply> <apply> <in /> <apply> <ci> Subscript </ci> <ci> &#945; </ci> <ci> k </ci> <ci> j </ci> </apply> <apply> <ci> SuperPlus </ci> <integers /> </apply> </apply> <apply> <leq /> <cn type='integer'> 1 </cn> <ci> k </ci> <cn type='integer'> 2 </cn> </apply> </apply> </apply> </annotation-xml> </semantics> </math>

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2001-10-29