Sum of Reciprocals of Powers as Euler Product/Corollary 1/Examples/Zeta(4) over Zeta(8)

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Example of Use of Sum of Reciprocals of Powers as Euler Product/Corollary 1

$\ds \prod_{\text {$p$ prime} } \paren {1 + p^{-4} } = \dfrac {105 } {\pi^4}$

where the infinite product runs over the prime numbers.


Proof

\(\ds \prod_{\text {$p$ prime} } \paren {1 + p^{-s} }\) \(=\) \(\ds \dfrac {\map \zeta s} {\map \zeta {2 s} }\) Sum of Reciprocals of Powers as Euler Product/Corollary 1
\(\ds \leadsto \ \ \) \(\ds \prod_{\text {$p$ prime} } \paren {1 + p^{-4} }\) \(=\) \(\ds \dfrac {\map \zeta 4} {\map \zeta 8}\)
\(\ds \) \(=\) \(\ds \dfrac {\dfrac {\pi^4 } {90} } {\dfrac {\pi^8} {9450} }\) Riemann Zeta Function of 4 and Riemann Zeta Function of 8
\(\ds \) \(=\) \(\ds \dfrac {9450} {90 \pi^4}\)
\(\ds \) \(=\) \(\ds \dfrac {105} {\pi^4}\)

$\blacksquare$