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ARITHMETIC-GEOMETRIC MEAN SEQUENCES OVER FINITE FIELDS $\mathbb {F}_q$, WHERE $q\equiv 5$ (mod 8)

Published online by Cambridge University Press:  27 February 2025

NATÁLIA BÁTOROVÁ
Affiliation:
Faculty of Mathematics and Physics, Charles University, Sokolovská 83, 186 75 Praha 8, Czech Republic e-mail: [email protected]
STEVAN GAJOVIĆ*
Affiliation:
Faculty of Mathematics and Physics, Charles University, Sokolovská 83, 186 75 Praha 8, Czech Republic

Abstract

Arithmetic-geometric mean sequences were already studied over the real and complex numbers, and recently, Griffin et al. [‘AGM and jellyfish swarms of elliptic curves’, Amer. Math. Monthly 130(4) (2023), 355–369] considered them over finite fields $\mathbb {F}_q$ for $q \equiv 3 \pmod 4$. We extend the definition of arithmetic-geometric mean sequences over $\mathbb {F}_q$ to $q \equiv 5 \pmod 8$. We explain the connection of these sequences with graphs and explore the properties of the graphs in the case where $q \equiv 5 \pmod 8$.

Type
Research Article
Copyright
© The Author(s), 2025. Published by Cambridge University Press on behalf of Australian Mathematical Publishing Association Inc.

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Footnotes

The second author was supported by the Czech Science Foundation GAČR, grant 21-00420M and a Junior Fund grant for postdoctoral positions at Charles University.

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