Home / Faculty / Nollen, Nathaniel

Nollen, Nathaniel

Assistant Professor
Email Addressnnollen@math.upd.edu.ph
RoomMath Building Annex 218-K
Research Interests
Number Theory. Number Systems. Algebra.
Academic Groups
  • Education
    • PhD Mathematics (2025)
      University of the Philippines Diliman

      Dissertation: Quaternion Numeration Systems
      Adviser: Jonathan Caalim, Ph.D.

    • MS Mathematics (2021)
      University of the Philippines Diliman

      Thesis: On the Periodicity of \((\alpha,\beta)\)-expansions and Quaternionic Rotational Beta Expansions
      Adviser: Jonathan Caalim, Ph.D.

    • BS Mathematics (2019)
      University of the Philippines Diliman

      Thesis: Numeration systems in \(n\) bases, Parry tuples and their conjugates
      Adviser: Jonathan Caalim, Ph.D.

  • Publications
    1. Caalim, J., Kaneko, H., & Nollen, N. (2025). Rotational beta expansions and Schmidt games. Acta Mathematica Hungarica, 176(2), 400–436. https://doi.org/10.1007/s10474-025-01555-x
    2. Caalim, J., & Nollen N. (2026). Periodic quaternion expansion in Pisot bases. Osaka Journal of Mathematics, 63(1), 123-140. https://doi.org/10.18910/103808