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# Talk: A solution of Sun's $520 challenge concerning 520/pi (Dublin) A solution of Sun's$520 challenge concerning 520/pi (Dublin)

Date: 2013/03/14
Occasion: 27th Automorphic Forms Workshop
Place: University College Dublin

## Abstract

Series for $$1/\pi$$ and their relation to modular forms have a long history going back to Ramanujan. We will review this connection and give a brief account of the history. We then indicate how to prove a Ramanujan-type formula for $$520/\pi$$ that was conjectured by Zhi-Wei Sun. A key ingredient is a hypergeometric representation of the relevant double series, which relies on a recent generating function for Legendre polynomials by James Wan and Wadim Zudilin.

This is joint work with Mathew D. Rogers.