Abstract
We prove that the edges of every even graph G=G 1+G 2 that is the join of two regular graphs G i =(V i ,E i ) can be coloured with Δ(G) colours, whenever Δ(G)=Δ(G 2)+|V 1|. The proof of this result yields a combinatorial algorithm to optimally colour the edges of this type of graphs.
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De Simone, C., Galluccio, A. Edge-colouring of joins of regular graphs, I. J Comb Optim 18, 417–428 (2009). https://doi.org/10.1007/s10878-009-9235-8
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DOI: https://doi.org/10.1007/s10878-009-9235-8