Abstract
Mock theta functions have been deeply studied in the literature. Historically, there are many forms of representations for mock theta functions: Eulerian forms, Hecke-type double sums, Appell–Lerch sums, and Fourier coefficients of meromorphic Jacobi forms. In this paper, we first establish Hecke-type double sums for the second and eighth order mock theta functions by Bailey’s lemma and a Bailey pair given by Andrews and Hickerson. Meanwhile, we give different proofs of the generalized Lambert series for the mock theta functions A(q), \(U_0(q)\), and \(U_1(q)\). Furthermore, using Ramanujan’s \({_1}\psi _1\) summation formula and a \({_2}\psi _2\) transformation formula due to Bailey, we prove some identities related to these mock theta functions.
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Andrews, G.E.: Mordell integrals and Ramanujan’s “lost” notebook. In: Knopp, M.I. (ed.) Analytic Number Theory. Lecture Notes in Mathematics, vol. 899. Springer, Berlin, Heidelberg (1981)
Andrews, G.E.: The fifth and seventh order mock theta functions. Trans. Am. Math. Soc. 293, 113–134 (1986)
Andrews, G.E.: \(q\)-Orthogonal polynomials, Rogers–Ramanujan identities, and mock theta functions. Proc. Steklov Inst. Math. 276, 21–32 (2012)
Andrews, G.E., Berndt, B.C.: Ramanujan’s Lost Notebook Part I. Springer, New York (2005)
Andrews, G.E., Hickerson, D.R.: Ramanujan’s “lost” notebook VII: the sixth order mock theta functions. Adv. Math. 89, 60–105 (1991)
Bailey, W.N.: On the basic bilateral hypergeometric series \(_2\psi_2\). Q. J. Math. 1, 194–198 (1950)
Bringmann, K., Hikami, K., Lovejoy, J.: On the modularity of the unified WRT invariants of certain Seifert manifolds. Adv. Appl. Math. 46, 86–93 (2011)
Choi, Y.S.: Tenth order mock theta functions in Ramanujan’s lost notebook. Invent. Math. 136, 497–569 (1999)
Choi, Y.S.: Tenth order mock theta functions in Ramanujan’s lost notebook II. Adv. Math. 156, 180–285 (2000)
Garvan, F.G.: Universal mock theta functions and two-variable Hecke–Rogers identities. Ramanujan J. 36, 267–296 (2015)
Gasper, G., Rahman, M.: Basic Hypergeometric Series, 2nd edn. Cambridge University Press, Cambridge (2004)
Gordon, B., McIntosh, R.J.: Some eighth order mock theta functions. J. Lond. Math. Soc. 62(2), 321–335 (2000)
Gordon, B., McIntosh, R.J.: A survey of classical mock theta functions, in “Partitions, \(q\)-series, and modular forms”. Adv. Math. 23, 95–144 (2012)
Hickerson, D.R., Mortenson, E.: Hecke-type double sums, Appell–Lerch sums, and mock theta functions, I. Proc. Lond. Math. Soc. 109(3), 382–422 (2014)
McIntosh, R.J.: Second order mock theta functions. Can. Math. Bull. 50, 284–290 (2007)
McIntosh, R.J.: New mock theta conjectures Part I. Ramanujan J. https://doi.org/10.1007/s11139-017-9938-x
Mortenson, E.: On the three third order mock theta functions and Hecke-type double sums. Ramanujan J. 30, 279–308 (2013)
Ramanujan, S.: Papers, Collected. Cambridge University Press, Chelsea, New York. Reprinted, p. 1962 (1927)
Ramanujan, S.: The Lost Notebook and Other Unpublished Papers. Narosa, New Delhi (1988)
Watson, G.N.: The final problem: an account of the mock theta functions. J. Lond. Math. Soc. 11, 55–80 (1936)
Watson, G.N.: The mock theta functions. Proc. Lond. Math. Soc. 42(2), 274–304 (1937)
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We would like to thank the referee for valuable suggestions.
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This work was supported by the National Natural Science Foundation of China and the Fundamental Research Funds for the Central Universities of China.
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Cui, SP., Gu, N.S.S. & Hao, LJ. On second and eighth order mock theta functions. Ramanujan J 50, 393–422 (2019). https://doi.org/10.1007/s11139-018-0045-4
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DOI: https://doi.org/10.1007/s11139-018-0045-4