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http://functions.wolfram.com/13.04.27.0005.01
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PrimePi[x] == -Sum[MoebiusMu[k] Sum[MoebiusMu[n] \[CapitalOmega][n]
Floor[x^(1/k)/n], {n, 2, Floor[x^(1/k)]}],
{k, 1, Floor[Log[2, x]]}] /;
n == Product[Subscript[p, k]^Subscript[n, k], {k, 1, l}] &&
Element[Subscript[p, k], Primes] && Element[Subscript[n, k], Integers] &&
Subscript[n, k] > 0 && \[CapitalOmega][n] == Sum[Subscript[n, k], {k, 1, l}]
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Cell[BoxData[RowBox[List[RowBox[List[RowBox[List["PrimePi", "[", "x", "]"]], "\[Equal]", RowBox[List["-", RowBox[List[UnderoverscriptBox["\[Sum]", RowBox[List["k", "=", "1"]], RowBox[List["Floor", "[", RowBox[List["Log", "[", RowBox[List["2", ",", "x"]], "]"]], "]"]]], RowBox[List[RowBox[List["MoebiusMu", "[", "k", "]"]], " ", RowBox[List[UnderoverscriptBox["\[Sum]", RowBox[List["n", "=", "2"]], RowBox[List["Floor", "[", SuperscriptBox["x", RowBox[List["1", "/", "k"]]], "]"]]], RowBox[List[RowBox[List["MoebiusMu", "[", "n", "]"]], " ", RowBox[List["\[CapitalOmega]", "[", "n", "]"]], " ", RowBox[List["Floor", "[", FractionBox[SuperscriptBox["x", RowBox[List["1", "/", "k"]]], "n"], "]"]]]]]]]]]]]]]], "/;", RowBox[List[RowBox[List["n", "\[Equal]", RowBox[List[UnderoverscriptBox["\[Product]", RowBox[List["k", "=", "1"]], "l"], 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[RowBox[List["\[CapitalOmega]", "[", "n", "]"]], "\[Equal]", RowBox[List[UnderoverscriptBox["\[Sum]", RowBox[List["k", "=", "1"]], "l"], SubscriptBox["n", "k"]]]]]]]]]]]
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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> <semantics> <mi> π </mi> <annotation encoding='Mathematica'> TagBox["\[Pi]", PrimePi] </annotation> </semantics> <mo> ( </mo> <mi> x </mi> <mo> ) </mo> </mrow> <mo> ⩵ </mo> <mrow> <mo> - </mo> <mrow> <munderover> <mo> ∑ </mo> <mrow> <mi> k </mi> <mo> = </mo> <mn> 1 </mn> </mrow> <mrow> <mo> ⌊ </mo> <mrow> <msub> <mi> log </mi> <mn> 2 </mn> </msub> <mo> ( </mo> <mi> x </mi> <mo> ) </mo> </mrow> <mo> ⌋ </mo> </mrow> </munderover> <mrow> <mrow> <semantics> <mi> μ </mi> <annotation encoding='Mathematica'> TagBox["\[Mu]", MoebiusMu] </annotation> </semantics> <mo> ( </mo> <mi> k </mi> <mo> ) </mo> </mrow> <mo> ⁢ </mo> <mrow> <munderover> <mo> ∑ </mo> <mrow> <mi> n </mi> <mo> = </mo> <mn> 2 </mn> </mrow> <mrow> <mo> ⌊ </mo> <msup> <mi> x </mi> <mrow> <mn> 1 </mn> <mo> / </mo> <mi> k </mi> </mrow> </msup> <mo> ⌋ </mo> </mrow> </munderover> <mrow> <mrow> <semantics> <mi> μ </mi> <annotation encoding='Mathematica'> TagBox["\[Mu]", MoebiusMu] </annotation> </semantics> <mo> ( </mo> <mi> n </mi> <mo> ) </mo> </mrow> <mo> ⁢ </mo> <mrow> <mi> Ω </mi> <mo> ⁡ </mo> <mo> ( </mo> <mi> n </mi> <mo> ) </mo> </mrow> <mo> ⁢ </mo> <mrow> <mo> ⌊ </mo> <mfrac> <msup> <mi> x </mi> <mrow> <mn> 1 </mn> <mo> / </mo> <mi> k </mi> </mrow> </msup> <mi> n </mi> </mfrac> <mo> ⌋ </mo> </mrow> </mrow> </mrow> </mrow> </mrow> </mrow> </mrow> <mo> /; </mo> <mrow> <mrow> <mi> n </mi> <mo> ⩵ </mo> <mrow> <munderover> <mo> ∏ </mo> <mrow> <mi> k </mi> <mo> = </mo> <mn> 1 </mn> </mrow> <mi> l </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> <mrow> <mi> Ω </mi> <mo> ⁡ </mo> <mo> ( </mo> <mi> n </mi> <mo> ) </mo> </mrow> <mo> ⩵ </mo> <mrow> <munderover> <mo> ∑ </mo> <mrow> <mi> k </mi> <mo> = </mo> <mn> 1 </mn> </mrow> <mi> l </mi> </munderover> <msub> <mi> n </mi> <mi> k </mi> </msub> </mrow> </mrow> </mrow> </mrow> <annotation-xml encoding='MathML-Content'> <apply> <ci> Condition </ci> <apply> <eq /> <apply> <ci> PrimePi </ci> <ci> x </ci> </apply> <apply> <times /> <cn type='integer'> -1 </cn> <apply> <sum /> <bvar> <ci> k </ci> </bvar> <lowlimit> <cn type='integer'> 1 </cn> </lowlimit> <uplimit> <apply> <floor /> <apply> <log /> <logbase> <cn type='integer'> 2 </cn> </logbase> <ci> x </ci> </apply> </apply> </uplimit> <apply> <times /> <apply> <ci> MoebiusMu </ci> <ci> k </ci> </apply> <apply> <sum /> <bvar> <ci> n </ci> </bvar> <lowlimit> <cn type='integer'> 2 </cn> </lowlimit> <uplimit> <apply> <floor /> <apply> <power /> <ci> x </ci> <apply> <times /> <cn type='integer'> 1 </cn> <apply> <power /> <ci> k </ci> <cn type='integer'> -1 </cn> </apply> </apply> </apply> </apply> </uplimit> <apply> <times /> <apply> <ci> MoebiusMu </ci> <ci> n </ci> </apply> <apply> <ci> Ω </ci> <ci> n </ci> </apply> <apply> <floor /> <apply> <times /> <apply> <power /> <ci> x </ci> <apply> <times /> <cn type='integer'> 1 </cn> <apply> <power /> <ci> k </ci> <cn type='integer'> -1 </cn> </apply> </apply> </apply> <apply> <power /> <ci> n </ci> <cn type='integer'> -1 </cn> </apply> </apply> </apply> </apply> </apply> </apply> </apply> </apply> </apply> <apply> <and /> <apply> <eq /> <ci> n </ci> <apply> <product /> <bvar> <ci> k </ci> </bvar> <lowlimit> <cn type='integer'> 1 </cn> </lowlimit> <uplimit> <ci> l </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> <eq /> <apply> <ci> Ω </ci> <ci> n </ci> </apply> <apply> <sum /> <bvar> <ci> k </ci> </bvar> <lowlimit> <cn type='integer'> 1 </cn> </lowlimit> <uplimit> <ci> l </ci> </uplimit> <apply> <ci> Subscript </ci> <ci> n </ci> <ci> k </ci> </apply> </apply> </apply> </apply> </apply> </annotation-xml> </semantics> </math>
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| Cell[BoxData[RowBox[List[RowBox[List["HoldPattern", "[", RowBox[List["PrimePi", "[", "x_", "]"]], "]"]], "\[RuleDelayed]", RowBox[List[RowBox[List["-", RowBox[List[UnderoverscriptBox["\[Sum]", RowBox[List["k", "=", "1"]], RowBox[List["Floor", "[", RowBox[List["Log", "[", RowBox[List["2", ",", "x"]], "]"]], "]"]]], RowBox[List[RowBox[List["MoebiusMu", "[", "k", "]"]], " ", RowBox[List[UnderoverscriptBox["\[Sum]", RowBox[List["n", "=", "2"]], RowBox[List["Floor", "[", SuperscriptBox["x", RowBox[List["1", "/", "k"]]], "]"]]], RowBox[List[RowBox[List["MoebiusMu", "[", "n", "]"]], " ", RowBox[List["\[CapitalOmega]", "[", "n", "]"]], " ", RowBox[List["Floor", "[", FractionBox[SuperscriptBox["x", RowBox[List["1", "/", "k"]]], "n"], "]"]]]]]]]]]]]], "/;", RowBox[List[RowBox[List["n", "\[Equal]", RowBox[List[UnderoverscriptBox["\[Product]", RowBox[List["k", "=", "1"]], "l"], 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[RowBox[List["\[CapitalOmega]", "[", "n", "]"]], "\[Equal]", RowBox[List[UnderoverscriptBox["\[Sum]", RowBox[List["k", "=", "1"]], "l"], SubscriptBox["n", "k"]]]]]]]]]]]]] |
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Date Added to functions.wolfram.com (modification date)
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