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  1. Corrigenda to the paper “Infinitary superperfect numbers”

    Article • Annales Mathematicae et Informaticae, January 2025, Annales Mathematicae et Informaticae - AMI

    Tomohiro Yamada

  2. Explicit sieve estimates and nonexistence of odd multiperfect numbers of a certain form

    Article • International Journal of Number Theory, July 2024, World Scientific Pub Co Pte Lt

    Tomohiro Yamada

  3. On a theorem of Kanold on odd perfect numbers

    Article • Indian Journal of Pure and Applied Mathematics, December 2023, Springer Science + Business Media

    Tomohiro Yamada

  4. On a problem of De Koninck

    Article • Moscow Journal of Combinatorics and Number Theory, September 2021, Mathematical Sciences Publishers

    Tomohiro Yamada

  5. On finiteness of odd superperfect numbers

    Article • August 2020, Cellule MathDoc/CEDRAM

    Tomohiro Yamada

  6. An analog of perfect numbers involving the unitary totient function

    Article • Journal of Number Theory, April 2020, Elsevier

    Tomohiro Yamada

  7. On Sinha's note on perfect numbers

    Article • Annales Universitatis Scientiarum Budapestinensis de Rolando Eötvös Nominatae Sectio computatorica, January 2020, Eotvos Lorand University (ELTE)

    Tomohiro Yamada

  8. A new upper bound for odd perfect numbers of a special form

    Article • Colloquium Mathematicum, January 2019, Institute of Mathematics, Polish Academy of Sciences

    Tomohiro Yamada

  9. The generalized Ramanujan-Nagell equation x^2+D=2^s p_1^k p_2^l

    Article • Glasgow Mathematical Journal, August 2018, Cambridge University Press

    Tomohiro Yamada

  10. On the simultaneous equations $\sigma(2^a)=p^{f_1}q^{g_1}$, $\sigma(3^b)=p^{f_2}q^{g_2}$, $\sigma(5^c)=p^{f_3}q^{g_3}$

    Article • Publicationes Mathematicae Debrecen, July 2018, University of Debrecen/ Debreceni Egyetem

    Tomohiro Yamada

  11. 2 and 9 are the only biunitary superperfect numbers

    Article • Annales Universitatis Scientiarum Budapestinensis de Rolando Eötvös Nominatae Sectio computatorica, January 2018, Eotvos Lorand University (ELTE)

    Tomohiro Yamada

  12. Addendum and corrigenda to the paper “Infinitary superperfect numbers”

    Article • Annales Mathematicae et Informaticae, January 2018, Annales Mathematicae et Informaticae - AMI

    Tomohiro Yamada

  13. A note on the paper by Bugeaud and Laurent “Minoration effective de la distance p-adique entre puissances de nombres algébriques”

    Article • Journal of Number Theory, September 2010, Elsevier

    Tomohiro Yamada

  14. ON THE DIOPHANTINE EQUATION

    Article • Glasgow Mathematical Journal, December 2008, Cambridge University Press

    Tomohiro Yamada

  15. Odd perfect numbers of a special form

    Article • Colloquium Mathematicum, January 2005, Institute of Mathematics, Polish Academy of Sciences

    Tomohiro Yamada