English

On a function of Ramanujan twisted by a logarithm

Number Theory 2025-02-05 v1 Classical Analysis and ODEs

Abstract

A two-term functional equation for an infinite series involving the digamma function and a logarithmic factor is derived. A modular relation on page 220 of Ramanujan's Lost Notebook as well as a corresponding recent result for the derivative of Deninger's function are two main ingredients in its derivation. An interesting integral H(x)\mathscr{H}(x), which is of independent interest, plays a prominent role in our functional equation. Several alternative representations for H(x)\mathscr{H}(x) are obtained.

Keywords

Cite

@article{arxiv.2502.02419,
  title  = {On a function of Ramanujan twisted by a logarithm},
  author = {Atul Dixit and Sumukha Sathyanarayana and N. Guru Sharan},
  journal= {arXiv preprint arXiv:2502.02419},
  year   = {2025}
}

Comments

13 pages, submitted for publication. Comments are welcome

R2 v1 2026-06-28T21:32:17.371Z