Worm Colorings

@article{Goddard2015WormC,
  title={Worm Colorings},
  author={Wayne Goddard and Kirsti Wash and Honghai Xu},
  journal={Discussiones Mathematicae Graph Theory},
  year={2015},
  volume={35},
  pages={571 - 584}
}
Abstract Given a coloring of the vertices, we say subgraph H is monochromatic if every vertex of H is assigned the same color, and rainbow if no pair of vertices of H are assigned the same color. Given a graph G and a graph F, we define an F-WORM coloring of G as a coloring of the vertices of G without a rainbow or monochromatic subgraph H isomorphic to F. We present some results on this concept especially as regards to the existence, complexity, and optimization within certain graph classes… 

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