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These are two famous identities of Ramanujan. Where can I find the proofs of them:

  1. $ \displaystyle \frac{1}{\pi} = \frac{2\sqrt{2}}{9801} \sum\limits_{k=0}^{\infty} \frac{(4k!)(1103 + 26390k)}{(k!)^{2} (396)^{4k}}$

  2. $\displaystyle \int\limits_{0}^{\infty} \frac{1 + x^{2}/(b+1)^{2}}{1+x^{2}/a^{2}} \times \frac{1+ x^{2}/(b+2)^{2}}{1 + x^{2}/(a+1)^{2}} \times \cdots dx= \frac{\sqrt{\pi}}{2} \times \frac{\Gamma(a+1) \Gamma(b+\frac{1}{2}) \Gamma(b-a+\frac{1}{2}}{\Gamma(a)\Gamma(b+\frac{1}{2} \Gamma(b-a+1)}$ for $0 < a < b+\frac{1}{2}$.

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    Hurrah! Motivation!2010-08-10

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Since you seem to be in Chennai, walk into any mathematics library and pick up the collected works of Ramanujan. That is the best. Or look into the notes edited by Bruce Berndt.