On ψ-quadratic k-tuples and their generalizations

Stoyan Dimitrov
Notes on Number Theory and Discrete Mathematics
Print ISSN 1310–5132, Online ISSN 2367–8275
Volume 32, 2026, Number 1, Pages 162–172
DOI: 10.7546/nntdm.2026.32.1.162-172
Full paper (PDF, 196 Kb)

Details

Authors and affiliations

Stoyan Dimitrov
¹ Faculty of Applied Mathematics and Informatics, Technical University of Sofia
Blvd. St.Kliment Ohridski 8, Sofia 1000, Bulgaria
² Department of Bioinformatics and Mathematical Modelling, Institute of Biophysics and Biomedical Engineering, Bulgarian Academy of Sciences
Acad. G. Bonchev Str., Bl. 105, Sofia 1113, Bulgaria

Abstract

In this paper, we introduce the notion of ψ-quadratic k-tuples. We establish the non-existence of ψ-quadratic pairs and provide a partial analysis of ψ-quadratic triples. We also give examples and propose generalizations of these new concepts.

Keywords

• Dedekind ψ(n) function
• ψ-quadratic k-tuples

2020 Mathematics Subject Classification

• 11A25
• 11D72

References

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Manuscript history

• Received: 29 September 2025
• Revised: 28 February 2026
• Accepted: 3 March 2026
• Online First: 6 March 2026

Copyright information

Ⓒ 2026 by the Author.
This is an Open Access paper distributed under the terms and conditions of the Creative Commons Attribution 4.0 International License (CC BY 4.0).