On the degree of the Birkhoff polytope graph

Document Type : Original Article

Authors

1 Department of Mathematics, Qom University of Technology, Qom, Iran.

2 Department of Mathematics, Institute for Advanced Studies in Basic Sciences (IASBS), Zanjan 45137-66731, Iran.

Abstract
The Birkhoff polytope graph can be considered as the Cayley graph of the symmetric group $S_n$ with respect to $\mathcal{C}_n$, the set of cycles in $S_n$. Since the degree of every Cayley graph is a natural bound on several parameters of the graph, in this note by presenting a formula for $|\mathcal{C}_n|$, the degree of the Birkhoff polytope graph, we prove that it is bounded from above by
$\lfloor e\big{(}(n-1)! +(n-2)!+(n-3)! +\cdots 1 \big{)}\rfloor$, where $e$ is the Neper number.

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Volume 7, Issue 1
Winter 2026
Pages 177-181

  • Receive Date 16 September 2025
  • Revise Date 27 December 2025
  • Accept Date 02 January 2026