Commutativity of the adjacency matrices of graphs

نویسندگان

  • Saieed Akbari
  • F. Moazami
  • A. Mohammadian
چکیده

We say that two graphs G1 and G2 with the same vertex set commute if their adjacency matrices commute. In this paper, we find all integers n such that the complete bipartite graph Kn, n is decomposable into commuting perfect matchings or commuting Hamilton cycles. We show that there are at most n−1 linearly independent commuting adjacency matrices of size n; and if this bound occurs, then there exists a Hadamard matrix of order n.

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عنوان ژورنال:
  • Discrete Mathematics

دوره 309  شماره 

صفحات  -

تاریخ انتشار 2009