Riemann zeta at even integers

Theorem

The following formula holds for even integers $n$ and $m \in \{1,2,3,\ldots\}$: $$\zeta(n)= \left\{ \begin{array}{ll} 0 &, \quad n=-2m, \\ -\dfrac{1}{2} &, \quad n=0 \\ \dfrac{(-1)^m B_m}{2m} &, \quad n=2m, \end{array} \right.$$ where $\zeta$ denotes Riemann zeta and $B_m$ denotes Bernoulli numbers.

References

• 1930: {{ #if: |{{{2}}}|Edward Charles Titchmarsh}}{{#if: |{{#if: |, [[Mathematician:{{{author2}}}|{{ #if: |{{{2}}}|{{{author2}}}}}]]{{#if: |, [[Mathematician:{{{author3}}}|{{ #if: |{{{2}}}|{{{author3}}}}}]]{{#if: |, [[Mathematician:{{{author4}}}|{{ #if: |{{{2}}}|{{{author4}}}}}]]{{#if: |, [[Mathematician:{{{author5}}}|{{ #if: |{{{2}}}|{{{author5}}}}}]] and [[Mathematician:{{{author6}}}|{{ #if: |{{{2}}}|{{{author6}}}}}]]| and [[Mathematician:{{{author5}}}|{{ #if: |{{{2}}}|{{{author5}}}}}]]}}| and [[Mathematician:{{{author4}}}|{{ #if: |{{{2}}}|{{{author4}}}}}]]}}| and [[Mathematician:{{{author3}}}|{{ #if: |{{{2}}}|{{{author3}}}}}]]}}| and [[Mathematician:{{{author2}}}|{{ #if: |{{{2}}}|{{{author2}}}}}]]}}|}}: [[Book:Edward Charles Titchmarsh/The Zeta-Function of Riemann{{#if: |/Volume {{{volume}}}|}}{{#if: |/{{{edpage}}}}}|The Zeta-Function of Riemann{{#if: |: Volume {{{volume}}}|}}{{#if: |: {{{eddisplay}}}|{{#if: | ({{{ed}}} ed.)}}}}]]{{#if: | (translated by [[Mathematician:{{{translated}}}|{{ #if: |{{{2}}}|{{{translated}}}}}]])}}{{#if: |, {{{publisher}}}|}}{{#if: |, ISBN {{{isbn}}}|}}{{#if: Riemann zeta as contour integral | ... (previous)|}}{{#if: Functional equation for Riemann zeta | ... (next)|}}{{#if: |: Entry: {{#if: |[[{{{entryref}}}|{{{entry}}}]]|{{{entry}}}}}|}}: § Introduction $(5)$