Opuscula Mathematica (Jun 2022)

The crossing numbers of join products of paths with three graphs of order five

  • Michal Staš,
  • Mária Švecová

DOI
https://doi.org/10.7494/OpMath.2022.42.4.635
Journal volume & issue
Vol. 42, no. 4
pp. 635 – 651

Abstract

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The main aim of this paper is to give the crossing number of the join product \(G^\ast+P_n\) for the disconnected graph \(G^\ast\) of order five consisting of the complete graph \(K_4\) and one isolated vertex, where \(P_n\) is the path on \(n\) vertices. The proofs are done with the help of a lot of well-known exact values for the crossing numbers of the join products of subgraphs of the graph \(G^\ast\) with the paths. Finally, by adding new edges to the graph \(G^\ast\), we are able to obtain the crossing numbers of the join products of two other graphs with the path \(P_n\).

Keywords