Motivation for Ramanujan’s mysterious π\pi formula

The following formula for π was discovered by Ramanujan:
1π=229801k=0(4k)!(1103+26390k)(k!)43964k

Does anyone know how it works, or what the motivation for it is?

Answer

Here’s an easy introduction to the basics, “Pi Formulas and the Monster Group“.

http://sites.google.com/site/tpiezas/0013

Update: Just to make this more intriguing, define the fundamental unit U29=5+292 and fundamental solutions to Pell equations,

(U29)3=70+1329,thus70229132=1

(U29)6=9801+182029,thus980122918202=1

26((U29)6+(U29)6)2=3964

then we can see those integers all over the formula as,

1π=229801k=0(4k)!k!4297013k+1103(3964)k

See also this MO post.

Attribution
Source : Link , Question Author : Nick Alger , Answer Author : Community

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