Abstract
In this note we consider \(s\)-chromatic polynomials for finite simplicial complexes. When \(s=1\), the \(1\)-chromatic polynomial is just the usual graph chromatic polynomial of the \(1\)-skeleton. In general, the \(s\)-chromatic polynomial depends on the \(s\)-skeleton and its value at \(r\) is the number of \((r,s)\)-colorings of the simplicial complex.
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Notes
The computations behind the examples of this note were carried out in the computer algebra system Magma [3].
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Acknowledgments
We thank Eric Babson whose questions, in November \(2011\) at the WATACBA workshop in Buenos Aires, led to this note.
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The first author was supported by the Danish National Research Foundation through the Centre for Symmetry and Deformation (DNRF92) and by VILLUM FONDEN through the network for Experimental Mathematics in Number Theory, Operator Algebras, and Topology.
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Møller, J.M., Nord, G. Chromatic Polynomials of Simplicial Complexes. Graphs and Combinatorics 32, 745–772 (2016). https://doi.org/10.1007/s00373-015-1578-6
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DOI: https://doi.org/10.1007/s00373-015-1578-6
Keywords
- Vertex coloring of simplicial complex
- \(s\)-chromatic polynomial
- \(s\)-chromatic lattice
- \(s\)-Stirling number of second kind
- Möbius function