Abstract
We derive a new special case C(q) of a general continued fraction recorded by Ramanujan in his Lost Notebook. We give a representation of the continued fraction C(q) as a quotient of Dedekind eta-function and then use it to prove modular identities connecting C(q) with each of the continued fractions \(C(-q)\), \(C(q^{2})\), \(C(q^{3})\), \(C(q^{5})\), \(C(q^{7})\), \(C(q^{11})\), \(C(q^{13})\) and \(C(q^{17})\). We also prove general theorems for the explicit evaluation of the continued fraction C(q) by using Ramanujan’s class invariants.
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Andrews, G.E., Berndt, B.C.: Ramanujan’s Lost Notebooks, Part I. Springer, New York (2005)
Andrews, G.E., Berndt, B.C.: Ramanujan’s Lost Notebooks, Part II. Springer, New York (2009)
Berndt, B.C.: Ramanujan’s Notebooks, Part III. Springer, New York (1991)
Berndt, B.C.: Ramanujan’s Notebooks, Part V. Springer, New York (1998)
Ramanujan, S.: Notebooks (2 Volumes). Tata Institute of Fundamental Research, Bombay (1957)
Ramanujan, S.: Collected Papers. Chelsea, New York (1962)
Ramanujan, S.: The Lost Notebook and Other Unpublished Papers. Narosa, New Delhi (1988)
Ramanujan, S.: Modular equations and approximations to \(\pi \). Q. J. Math. 45, 350–372 (1914)
Saikia, N.: Ramanujan’s Schläfli-type modular equations and class invariants \(g_{n}\). Funct. Approx. Comment. Math. 49(2), 201–409 (2013)
Saikia, N.: Ramanujan’s modular equations and Weber–Ramanujan’s class invariants \(G_{n}\) and \(g_{n}\). Bull. Math. Sci. 2, 205–223 (2012)
Saikia, N.: A parameter for Ramanujans function \(\chi (q)\): its explicit values and applications. ISRN Comput. Math. 2012, Article ID 169050 (2012)
Weber, H.: Lehrburg der Algebra II. Chelsea, New York (1961)
Acknowledgements
The first author (N. Saikia) is thankful to Council of Scientific and Industrial Research of India for partially supporting the research work under the Research Scheme No. 25(0241)/15/EMR-II [F. No. 25(5498)/15]. The authors also thank anonymous refree for his/her valuable suggestions and comments.
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Saikia, N., Boruah, C. Some results on a special case of a general continued fraction of Ramanujan. Ann Univ Ferrara 64, 165–183 (2018). https://doi.org/10.1007/s11565-017-0283-1
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DOI: https://doi.org/10.1007/s11565-017-0283-1