"모든 자연수의 곱과 리만제타함수"의 두 판 사이의 차이

수학노트
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<math>\zeta(s)=\frac{\pi^{-(1-s)/2}\ \Gamma\left(\frac{1-s}{2}\right)\ \zeta(1-s)}{\pi^{-s/2}\ \Gamma\left(\frac{s}{2}\right)}=\frac{\pi^{s-1/2}\ \Gamma\left(\frac{1-s}{2}\right)\ \zeta(1-s)}{\Gamma\left(\frac{s}{2}\right)}</math>
 
<math>\zeta(s)=\frac{\pi^{-(1-s)/2}\ \Gamma\left(\frac{1-s}{2}\right)\ \zeta(1-s)}{\pi^{-s/2}\ \Gamma\left(\frac{s}{2}\right)}=\frac{\pi^{s-1/2}\ \Gamma\left(\frac{1-s}{2}\right)\ \zeta(1-s)}{\Gamma\left(\frac{s}{2}\right)}</math>
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<math>f(s)=s\zeta(1-s)</math> 라 두자.
 
<math>f(s)=s\zeta(1-s)</math> 라 두자.
  
<math>f(s)=s\zeta(1-s)</math> 
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<math>s=0</math> 주변에서 <math>f(s)=-1+\gamma s+O(s^2)</math> 이다. 
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<math>\zeta(s)=\frac{1}{s-1}+\gamma+O((s-1)^2)</math> 를 이용.
  
 
 
 
 
  
 
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<math>\zeta(s)=\frac{\pi^{s-1/2}\ \Gamma(\frac{1-s}{2})f(s)}{2\Gamma(\frac{s}{2}+1)}</math>
  
<math>\zeta(s)=\frac{1}{s-1}+\gamma+O(|s-1|)</math>로부터
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<math>s=0</math> 에서의 로그미분값을 계산하면
  
<math>f(s)=s\zeta(1-s)</math>
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<math>\frac{\zeta'(0)}{\zeta(0)}=\log\pi-\frac{1}{2}\frac{\Gamma'(\frac{1}{2})}{\Gamma(\frac{1}{2})}+\frac{f'(0)}{f(0)}-\frac{1}{2}\frac{\Gamma'(1)}{\Gamma(1)</math>
  
 
 
 
 

2009년 7월 4일 (토) 19:42 판

간단한 소개
  • \(\zeta'(0)=-\log{\sqrt{2\pi}}\)

 

 

 

증명
  • 감마함수의 성질
    \(\Gamma(z) \; \Gamma\left(z + \frac{1}{2}\right) = 2^{\frac{1}{2}-2z} \; \sqrt{2\pi} \; \Gamma(2z) \,\!\)
  • 리만제타함수의 함수방정식
    \(\zeta(s)=\frac{\pi^{-(1-s)/2}\ \Gamma\left(\frac{1-s}{2}\right)\ \zeta(1-s)}{\pi^{-s/2}\ \Gamma\left(\frac{s}{2}\right)}=\frac{\pi^{s-1/2}\ \Gamma\left(\frac{1-s}{2}\right)\ \zeta(1-s)}{\Gamma\left(\frac{s}{2}\right)}\)
  • 을 이용한다.

 

\(\zeta(s)=\frac{\pi^{-(1-s)/2}\ \Gamma\left(\frac{1-s}{2}\right)\ \zeta(1-s)}{\pi^{-s/2}\ \Gamma\left(\frac{s}{2}\right)}=\frac{\pi^{s-1/2}\ \Gamma\left(\frac{1-s}{2}\right)\ \zeta(1-s)}{\Gamma\left(\frac{s}{2}\right)}\)

 

\(f(s)=s\zeta(1-s)\) 라 두자.

\(s=0\) 주변에서 \(f(s)=-1+\gamma s+O(s^2)\) 이다. 

\(\zeta(s)=\frac{1}{s-1}+\gamma+O((s-1)^2)\) 를 이용.

 

\(\zeta(s)=\frac{\pi^{s-1/2}\ \Gamma(\frac{1-s}{2})f(s)}{2\Gamma(\frac{s}{2}+1)}\)

\(s=0\) 에서의 로그미분값을 계산하면, 

\(\frac{\zeta'(0)}{\zeta(0)}=\log\pi-\frac{1}{2}\frac{\Gamma'(\frac{1}{2})}{\Gamma(\frac{1}{2})}+\frac{f'(0)}{f(0)}-\frac{1}{2}\frac{\Gamma'(1)}{\Gamma(1)} \)