Some Nonlinear Identities for Divisor Functions

  • M. Ram Murty
  • V. Kumar Murty


In his 1916 paper, Ramanujan derived a series of nonlinear identities for a class of divisor functions. We now know that these identities arise as a consequence of the low dimension of certain spaces of modular forms. In this chapter, we explain these identities as well as indicate the relation to the theory of quasi-modular forms.


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Copyright information

© Springer India 2013

Authors and Affiliations

  • M. Ram Murty
    • 1
  • V. Kumar Murty
    • 2
  1. 1.Department of Mathematics and StatisticsQueen’s UniversityKingstonCanada
  2. 2.Department of MathematicsUniversity of TorontoTorontoCanada

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