Abstract
Applying the multiplicate forms of Gould–Hsu inverse series relations to the Pfaff–Saalschütz summation theorem, we establish several infinite series expressions for \(\pi \) and \(1/\pi \), including three typical ones due to Ramanujan (Journal of Mathematics 45:350–372, 1914)
Similar content being viewed by others
References
Adamchik, V., Wagon, S.: \(\pi \): a 2000-year search changes direction. Math. Educ. Res. 5(1), 11–19 (1996)
Bailey, W.N.: Generalized Hypergeometric Series. Cambridge University Press, Cambridge (1935)
Baruah, N.D., Berndt, B.C., Chan, H.H.: Ramanujan’s series for \(1/\pi \): a survey. Am. Math. Monthly 116, 567–587 (2009)
Borwein, J.M., Borwein, P.B.: Pi and the AGM: A Study in Analytic Number Theory and Computational Complexity. Wiley, New York (1987)
Bressoud, D.M.: A matrix inverse. Proc. Amer. Math. Soc. 88(3), 446–448 (1983)
Brychkov, YuA: Handbook of Special Functions: Derivatives, Integrals. Series and Other Formulas. CRC Press, Boca Raton, FL (2008)
Carlitz, L.: Some inverse series relations. Duke Math. J. 40, 893–901 (1973)
Chen, X., Chu, W.: Closed formulae for a class of terminating \(_3F_2(4)\)-series. Integral Transforms Spec. Funct. 28(11), 825–837 (2017)
Chen, X., Chu, W.: Terminating \(_3F_2(4)\)-series extended with three integer parameters. J. Differ. Equ. Appl. 24(8), 1346–1367 (2018)
Chen, X., Chu, W.: Multiplicate inversions and identities of terminating hypergeometric series. Util. Math. 90, 115–133 (2013)
Chu, W.: Inversion techniques and combinatorial identities. Boll. Un. Mat. Ital. B-7, Serie VII, 737–760 (1993)
Chu, W.: Inversion techniques and combinatorial identities: strange evaluations of hypergeometric series. Pure Math. Appl. 4(4), 409–428 (1993)
Chu, W.: Inversion techniques and combinatorial identities: a quick introduction to hypergeometric evaluations. Math. Appl. 283, 31–57 (1994)
Chu, W.: Inversion techniques and combinatorial identities: basic hypergeometric identities. Publ. Math. Debrecen 44(3/4), 301–320 (1994)
Chu, W.: Inversion techniques and combinatorial identities: strange evaluations of basic hypergeometric series. Compos. Math. 91, 121–144 (1994)
Chu, W.: Inversion techniques and combinatorial identities: a unified treatment for the \(_7F_6\)-series identities. Collect. Math. 45(1), 13–43 (1994)
Chu, W.: Inversion techniques and combinatorial identities: Jackson’s \(q\)-analogue of the Dougall–Dixon theorem and the dual formulae. Compos. Math. 95, 43–68 (1995)
Chu, W.: Inversion techniques and combinatorial identities: balanced hypergeometric series. Rocky Mt. J. Math. 32(2), 561–587 (2002)
Chu, W.: \(q\)-Derivative operators and basic hypergeometric series. Results Math. 49(1–2), 25–44 (2006)
Chu, W.: \(\pi \)-formulas implied by Dougall’s summation theorem for \(_5F_4\)-series. Ramanujan J. 26(2), 251–255 (2011)
Chu, W.: Dougall’s bilateral \(_2H_2\)-series and Ramanujan-like \(\pi \)-formulae. Math. Comp. 80(276), 2223–2251 (2011)
Chu, W.: \(q\)-series reciprocities and further \(\pi \)-formulae. Kodai Math. J. 41(3), 512–530 (2018)
Chu, W., Wang, C.Y.: Bilateral inversions and terminating basic hypergeometric series identities. Discrete Math. 309(12), 3888–3904 (2009)
Chu, W., Wang, X.: Summation formulae on Fox–Wright \(\Psi \)-functions. Integral Transforms Spec. Funct. 19(8), 545–561 (2008)
Chu, W., Zhang, W.: Accelerating Dougall’s \(_5F_4\)-sum and infinite series involving \(\pi \). Math. Comp. 83(285), 475–512 (2014)
Gessel, I., Stanton, D.: Strange evaluations of hypergeometric series. SIAM J. Math. Anal. 13, 295–308 (1982)
Gessel, I., Stanton, D.: Applications of \(q\)-Lagrange inversion to basic hypergeometric series. Trans. Am. Math. Soc. 277(1), 173–201 (1983)
Gessel, I., Stanton, D.: Another family of \(q\)-Lagrange inversion formulas. Rocky Mt. J. Math. 16(2), 373–384 (1986)
Glaisher, J.W.L.: On series for \(1/\pi \) and \(1/\pi ^2\). Quart. J. Pure Appl. Math. 37, 173–198 (1905)
Gould, H.W., Hsu, L.C.: Some new inverse series relations. Duke Math. J. 40, 885–891 (1973)
Guillera, J.: About a new kind of Ramanujan-type series. Exp. Math. 12(4), 507–510 (2003)
Guillera, J.: Generators of some Ramanujan formulas. Ramanujan J. 11(1), 41–48 (2006)
Guillera, J.: Hypergeometric identities for 10 extended Ramanujan-type series. Ramanujan J. 15(2), 219–234 (2008)
Guillera, J.: Dougall’s \(_5F_4\) sum and the WZ algorithm. Ramanujan J. 46(3), 667–675 (2018)
Guillera, J.: Proofs of some Ramanujan series for \(1/\pi \) using a program due to Zeilberger. J. Differ. Equ. Appl. 24(10), 1643–1648 (2018)
Hardy, G.H.: Some formulae of Ramanujan. Proc. Lond. Math. Soc. 22, 12–13 (1924)
Rainville, E.D.: Special Functions. The Macmillan Company, New York (1960)
Ramanujan, S.: Modular equations and approximations to \(\pi \). Quart. J. Math. 45, 350–372 (1914)
Slater, L.J.: Generalized Hypergeoemtric Functions. Cambridge University Press, Cambridge (1966)
Stromberg, K.R.: An Introduction to Classical Real Analysis. Wadsworth. INC., Belmont, CA (1981)
Author information
Authors and Affiliations
Corresponding author
Additional information
In memory of my teacher Professor L. C. Hsu.
Publisher's Note
Springer Nature remains neutral with regard to jurisdictional claims in published maps and institutional affiliations.
Rights and permissions
About this article
Cite this article
Chu, W. Ramanujan-like formulae for \(\pi \) and \(1/\pi \) via Gould–Hsu inverse series relations. Ramanujan J 56, 1007–1027 (2021). https://doi.org/10.1007/s11139-020-00337-z
Received:
Accepted:
Published:
Issue Date:
DOI: https://doi.org/10.1007/s11139-020-00337-z
Keywords
- Classical hypergeometric series
- Pfaff–Saalschütz summation theorem
- Gould–Hsu inverse series relations
- Infinite series expression for \(\pi \)
- Ramanujan’s series for \(1/\pi \)