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Some modular identities of Ramanujan useful in approximating $ \pi$

Author: Jon Borwein
Journal: Proc. Amer. Math. Soc. 95 (1985), 365-371
MSC: Primary 11F03; Secondary 11J72, 41A25
MathSciNet review: 806072
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Abstract: We show how various modular identities due to Ramanujan may be used to produce simple high order approximations to $ \pi $. Various specializations are considered and the Gaussian arithmetic geometric mean formula for $ \pi $ is rederived as a consequence.

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Article copyright: © Copyright 1985 American Mathematical Society