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Difference between revisions of "Mangoldt function"

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The [[Arithmetic function|arithmetic function]] defined by
 
The [[Arithmetic function|arithmetic function]] defined by
 
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$$
<table class="eq" style="width:100%;"> <tr><td valign="top" style="width:94%;text-align:center;"><img align="absmiddle" border="0" src="https://www.encyclopediaofmath.org/legacyimages/m/m062/m062200/m0622001.png" /></td> </tr></table>
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\Lambda(n) = \begin{cases} \log p &\mbox{if } n = p^m,\,p \mbox{ prime},\,m\ge 1 \\
 
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0 & \mbox{otherwise} . \end{cases}
The function <img align="absmiddle" border="0" src="https://www.encyclopediaofmath.org/legacyimages/m/m062/m062200/m0622002.png" /> has the following properties:
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$$
 
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The function $\Lambda(n)$ has the following properties:
<table class="eq" style="width:100%;"> <tr><td valign="top" style="width:94%;text-align:center;"><img align="absmiddle" border="0" src="https://www.encyclopediaofmath.org/legacyimages/m/m062/m062200/m0622003.png" /></td> </tr></table>
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$$
 
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\sum_{d | n} \Lambda(d) = \log n \,,
<table class="eq" style="width:100%;"> <tr><td valign="top" style="width:94%;text-align:center;"><img align="absmiddle" border="0" src="https://www.encyclopediaofmath.org/legacyimages/m/m062/m062200/m0622004.png" /></td> </tr></table>
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$$
 
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where $\mu$ denotes the [[Möbius function]], and so by [[Möbius inversion]]
where the sums are taken over all divisors <img align="absmiddle" border="0" src="https://www.encyclopediaofmath.org/legacyimages/m/m062/m062200/m0622005.png" /> of <img align="absmiddle" border="0" src="https://www.encyclopediaofmath.org/legacyimages/m/m062/m062200/m0622006.png" />. The Mangoldt function is closely connected with the Riemann [[Zeta-function|zeta-function]] <img align="absmiddle" border="0" src="https://www.encyclopediaofmath.org/legacyimages/m/m062/m062200/m0622007.png" />. In fact, the generating series for <img align="absmiddle" border="0" src="https://www.encyclopediaofmath.org/legacyimages/m/m062/m062200/m0622008.png" /> is the logarithmic derivative of <img align="absmiddle" border="0" src="https://www.encyclopediaofmath.org/legacyimages/m/m062/m062200/m0622009.png" />:
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$$
 
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\Lambda(n) = \sum_{d|n} \mu(d) \log(n/d)
<table class="eq" style="width:100%;"> <tr><td valign="top" style="width:94%;text-align:center;"><img align="absmiddle" border="0" src="https://www.encyclopediaofmath.org/legacyimages/m/m062/m062200/m06220010.png" /></td> </tr></table>
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$$
 
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where the sums are taken over all divisors $d$ of $n$. The Mangoldt function is closely connected with the Riemann [[Zeta-function|zeta-function]] $\zeta(s)$. In fact, the generating series for $\Lambda(n)$ is the logarithmic derivative of $\zeta(s)$:
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$$
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-\frac{\zeta'(s)}{\zeta(s)} = \sum_n \Lambda(n) n^{-s}\ \ \ (\Re s > 1)
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$$
 
The Mangoldt function was proposed by H. Mangoldt in 1894.
 
The Mangoldt function was proposed by H. Mangoldt in 1894.
  
  
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====References====
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<table>
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<TR><TD valign="top">[a1]</TD> <TD valign="top">  G.H. Hardy,  E.M. Wright,  "An introduction to the theory of numbers" , Oxford Univ. Press  (1979)  pp. Sect. 17.7</TD></TR>
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</table>
  
====Comments====
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{{TEX|done}}
In the article above, <img align="absmiddle" border="0" src="https://www.encyclopediaofmath.org/legacyimages/m/m062/m062200/m06220011.png" /> denotes the [[Möbius function|Möbius function]].
 
  
====References====
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[[Category:Number theory]]
<table><TR><TD valign="top">[a1]</TD> <TD valign="top">  G.H. Hardy,  E.M. Wright,  "An introduction to the theory of numbers" , Oxford Univ. Press  (1979)  pp. Sect. 17.7</TD></TR></table>
 

Latest revision as of 18:33, 18 October 2014

The arithmetic function defined by $$ \Lambda(n) = \begin{cases} \log p &\mbox{if } n = p^m,\,p \mbox{ prime},\,m\ge 1 \\ 0 & \mbox{otherwise} . \end{cases} $$ The function $\Lambda(n)$ has the following properties: $$ \sum_{d | n} \Lambda(d) = \log n \,, $$ where $\mu$ denotes the Möbius function, and so by Möbius inversion $$ \Lambda(n) = \sum_{d|n} \mu(d) \log(n/d) $$ where the sums are taken over all divisors $d$ of $n$. The Mangoldt function is closely connected with the Riemann zeta-function $\zeta(s)$. In fact, the generating series for $\Lambda(n)$ is the logarithmic derivative of $\zeta(s)$: $$ -\frac{\zeta'(s)}{\zeta(s)} = \sum_n \Lambda(n) n^{-s}\ \ \ (\Re s > 1) $$ The Mangoldt function was proposed by H. Mangoldt in 1894.


References

[a1] G.H. Hardy, E.M. Wright, "An introduction to the theory of numbers" , Oxford Univ. Press (1979) pp. Sect. 17.7
How to Cite This Entry:
Mangoldt function. Encyclopedia of Mathematics. URL: http://encyclopediaofmath.org/index.php?title=Mangoldt_function&oldid=14110
This article was adapted from an original article by S.A. Stepanov (originator), which appeared in Encyclopedia of Mathematics - ISBN 1402006098. See original article