Abstract
In a search for triangle-free graphs with arbitrarily large chromatic number, Mycielski developed a graph transformation that transforms a graph G into a new graph μ(G), which is called the Mycielskian of G. A generalisation of this transformation is the generalised Mycielskian μ m (G), m a positive integer. This paper investigates the vertex-connectivity κ and arc-connectivity κ′ of the generalised Mycielskian of strongly connected digraphs D. We show that κ (μ m (D)) = min{δ(μ m (D)), (m + 1)κ (D) + 1} and κ′ (μ m (D)) = δ(μ m (D)) where δ(μ m (D)) denotes the minimum degree of the generalised Mycielisian μ m (D). This turns out to be a generalisation of the results due to Guo and Guo (Appl. Math. Lett. 22:1622–1625, 2009).
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Francis Raj, S. Connectivity of the Generalised Mycielskian of Digraphs. Graphs and Combinatorics 29, 893–900 (2013). https://doi.org/10.1007/s00373-012-1151-5
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DOI: https://doi.org/10.1007/s00373-012-1151-5