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q-Analogues of three Ramanujan-type formulas for \(1/\pi \)

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Abstract

We give q-analogues of three Ramanujan-type series for \(1/\pi \) from q-analogues of ordinary WZ pairs. The first one is a new q-analogue of the following Ramanujan’s formula for \(1/\pi \):

$$\begin{aligned} \sum _{n=0}^\infty \frac{6n+1}{256^n}{2n\atopwithdelims ()n}^3=\frac{4}{\pi }, \end{aligned}$$

of which another q-analogue was given by the author and Liu early and reproved by different authors. We also present a WZ proof of a q-analogue of Bauer’s (Ramanujan-type) formula and discuss some related congruences and q-congruences.

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Notes

  1. Doron Zeilberger’s computer servant.

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Acknowledgements

The author would like to thank the anonymous referee for helpful comments on a previous version of this paper.

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Correspondence to Victor J. W. Guo.

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This work was partially supported by the National Natural Science Foundation of China (Grant 11771175)

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Guo, V.J.W. q-Analogues of three Ramanujan-type formulas for \(1/\pi \). Ramanujan J 52, 123–132 (2020). https://doi.org/10.1007/s11139-018-0096-6

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