 |
for ![|I[z]|<pi/2](/images/equations/RamanujansFormula/Inline1.svg)
.
A related integral is
 |
for ![|R[z]|<pi/2](/images/equations/RamanujansFormula/Inline2.svg)
.
Ramanujan's Formula
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References
Erdélyi, A.; Magnus, W.; Oberhettinger, F.; and Tricomi, F. G. Higher Transcendental Functions, Vol. 1. New York: Krieger, p. 11, 1981.Referenced on Wolfram|Alpha
Ramanujan's FormulaCite this as:
Weisstein, Eric W. "Ramanujan's Formula." From MathWorld--A Wolfram Web Resource. https://mathworld.wolfram.com/RamanujansFormula.html