The structure of power digraph connected with the congruence a¹¹ ≡ b(mod n)

Authors

  • Pinkimani Goswami University of Science and Technology.
  • Sanjay Kumar Thakur Science College.
  • Gautam Chandra Ray Central Institute of Technology Kokrajhar.

DOI:

https://doi.org/10.22199/issn.0717-6279-5600

Keywords:

digraph, fixed point, power digraph, regular graph, Carmichael λ-function

Abstract

We assign to each positive integer n a digraph Γ(n, 11) whose set of vertices is Zn = {0, 1, 2, ..., n − 1} and there exists exactly one directed edge from a to b if and only if a11 ≡ b(mod n), where a, b ∈ Zn. Let Γ1(n, 11) be the subdigraph induced by the vertices which are coprime to n. We discuss when the subdigraph Γ1(n, 11) is regular or semi-regular. A formula for the number of fixed points of Γ(n, 11) is established. A necessary and sufficient condition for the symmetry of the digraph Γ(n, 11) is proved. Moreover, using Carmichael ́s lambda function, the number of components and conditions for the existence of cycles in the digraph Γ(n, 11) is presented.

Author Biographies

Pinkimani Goswami , University of Science and Technology.

Department of Mathematics.

Sanjay Kumar Thakur , Science College.

Assitant Professor, Department of Mathematics.

Gautam Chandra Ray, Central Institute of Technology Kokrajhar.

Department of Mathematics.

References

E. Blanton Jr., S. Hurd, and J. McCranie, “On a digraph defined by square modulo n”, Fibonacci Quarterly, vol. 34, pp. 322-334, 1992. [On line]. Available: https://bit.ly/40jRuyh

S. Bryant, “Groups, graphs and Fermat’s last theorem”, The American Mathematical Monthly, vol. 74, pp. 152-156, 1967. doi: 10.2307/2315605

D. M. Burton, Elementary Number Theory, 7th ed. Tata McGraw-Hill, 2012.

R. D. Carmichael, “Note on a new number function”, Bulletin of American Mathematical Society, vol. 16, pp. 233-238, 1910. https://doi.org/10.1090/S0002-9904-1910-01892-9

F. Harary, Graph theory. London: Addison-Wesley, 1969.

M. H. Mateen and M. K. Mahmood, “Power Digraphs Associated with the Congruence xᵏ ≡ y(mod n)”, Punjab University Journal of Mathematics, vol. 51, pp. 93-102, 2019. [On line]. Available: https://bit.ly/3JxUNuX

M. H. Mateen, M. K. Mahmood, D. Alghazzawi and J. Liu, “Structures of power digraphs over the congruence equation xᵖ ≡ y(mod m) and enumerations,” AIMS Mathematics, vol. 6, no. 5, pp. 4581-4596, 2021. https://doi.org/10.3934/math.2021270

K. Ireland and M. Rosen, “Graduate Texts in Mathematics: A classical introduction to modern number theory”, 2nd ed. Springer, 1990.

M. Krizek, F. Luca and L. Somer, 17 Lectures on Fermat Numbers: From Number theory to Geometry. New York: Springer, 2001.

M. Krizek and L. Somer, “Sophie Germain little suns”, Mathematica Slovaca, vol. 54, no. 5, pp. 433-442, 2004.

C. Lucheta, E. Miller and C. Reiter, “Digraphs from Powers modulo p”, Fibonacci Quart, vol. 34, pp. 226-239, 1996. [On line]. Available: https://bit.ly/40iC0e2

M. Rahmati, “Some digraphs attached with congruence x⁵ ≡y(mod n)”, Journal of Mathematical Extension, vol. 11, no. 1, pp. 47-56, 2017. [On line]. Available: https://bit.ly/402YD6D

J. Skowronek-Kaziow and Z. Gora, “Properties of digraphs connected with some congruence relations”, Czechoslovak Mathematical Journal, vol. 59, pp. 39-49, 2009. https://doi.org/10.1007/s10587-009-0003-9

L. Somer and M. Krizek, “On a connection of number theory with graph theory”, Czechoslovak Mathematical Journal, vol. 54, pp. 465-485, 2004. https://doi.org/10.1023/B:CMAJ.0000042385.93571.58

L. Somer and M. Krizek, “The structure of digraphs associated with the congruence xᵏ ≡ y(mod n)”, Czechoslovak Mathematical Journal, vol. 61, pp. 337-358, 2011. doi: 10.1007/s10587-011-0079-x

L. Szalay, “A discrete iteration in number theory”, BDTF Tud. Kozl., vol. 8, pp. 71-91, 1992.

Published

2023-03-27

How to Cite

[1]
P. . Goswami, Sanjay Kumar Thakur, and G. C. Ray, “The structure of power digraph connected with the congruence a¹¹ ≡ b(mod n)”, Proyecciones (Antofagasta, On line), vol. 42, no. 2, pp. 457-477, Mar. 2023.

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Section

Artículos