Proof of a conjecture for the watching number

Document Type : Full Length Article

Authors

1 ‎Department of Basic Science, ‎Imam Khomeini International University‎‎,‎Qazvin‎, ‎Iran

2 ‎Department of Pure Mathematics, ‎Faculty of Mathematical Sciences‎, ‎University of Guilan‎‎, ‎Rasht‎, ‎Iran

3 Faculty of Mathematical Sciences, University of Guilan, Rasht, Iran

Abstract

In this paper, we prove that for every connected graph G of order n, the watching number of its subdivision graph S(G) is exactly n. This result confirms a conjecture previously proposed by Vatandoost et al. [7].

Graphical Abstract

Proof of a conjecture for the watching number

Keywords

Main Subjects


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Volume 11, Issue 3
September 2026
Pages 193-198
  • Receive Date: 22 October 2025
  • Revise Date: 09 February 2026
  • Accept Date: 09 March 2026
  • First Publish Date: 30 August 2026
  • Publish Date: 01 September 2026