Krassimir Atanassov and József Sándor
Notes on Number Theory and Discrete Mathematics
Print ISSN 1310–5132, Online ISSN 2367–8275
Volume 32, 2026, Number 1, Pages 207–213
DOI: 10.7546/nntdm.2026.32.1.207-213
Full paper (PDF, 167 Kb)
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Authors and affiliations
Krassimir Atanassov
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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
József Sándor
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Department of Mathematics, Babeș-Bolyai University
Str. Kogălniceanu nr. 1, 400084 Cluj-Napoca, Romania
Abstract
Two arithmetic operations are introduced and some of their properties are studied. It is proved that they can be operations of semi-groups, but not of monoids. It is shown that their reverse operations are not one-valued. Some connections between the new operations and the well-known arithmetic functions
are shown.
Keywords
- Arithmetic function
- Arithmetic operation
- Semi-group
2020 Mathematics Subject Classification
- 11A99
References
- Atanassov, K. (2002). Restrictive factor: Definition, properties and problems. Notes on Number Theory and Discrete Mathematics, 8(4), 117–119.
- Atanassov, K. (2016). On function “Restrictive factor”. Notes on Number Theory and Discrete Mathematics, 22(2), 17–22.
- Panaitopol, L. (2004). Properties of the Atanassov functions. Advanced Studies on Contemporary Mathematics, 8(1), 55–59.
- Sándor, J., & Atanassov, K. (2020). Restrictive factor and extension factor. Notes on Number Theory and Discrete Mathematics, 26(2), 34–46.
- Sándor, J., & Atanassov, K. (2021). Arithmetic Functions. Nova Sciences, New York.
Manuscript history
- Received: 3 November 2025
- Revised: 5 March 2026
- Accepted: 18 March 2026
- Online First: 19 March 2026
Copyright information
Ⓒ 2026 by the Authors.
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).
Related papers
- Sándor, J., & Atanassov, K. (2020). Restrictive factor and extension factor. Notes on Number Theory and Discrete Mathematics, 26(2), 34–46.
- Atanassov, K. (2016). On function “Restrictive factor”. Notes on Number Theory and Discrete Mathematics, 22(2), 17–22.
- Panaitopol, L., (2003). Properties of the restrictive factor. Notes on Number Theory and Discrete Mathematics, 9(3), 59–61.
- Atanassov, K. (2002). Restrictive factor: Definition, properties and problems. Notes on Number Theory and Discrete Mathematics, 8(4), 117–119.
Cite this paper
Atanassov, K., & Sándor, J. (2026). Two new arithmetic operations. Notes on Number Theory and Discrete Mathematics, 32(1), 207-213, DOI: 10.7546/nntdm.2026.32.1.207-213.
