2021/12/05 by Ichihara, Kazuhiro, Matsudo, Eri
#FOS: Mathematics #Geometric Topology (math.GT)
paper · doi:10.48550/arxiv.2112.02515
We consider the number of colors for the colorings of links by the symmetric group S3 of degree 3. For knots, such a coloring corresponds to a Fox 3-coloring, and thus the number of colors must be 1 or 3. However, for links, there are colorings by S3 with 4 or 5 colors. In this paper, we show that if a 2-bridge link admits a coloring by S3 with 5 colors, then the link also admits such a coloring with only 4 colors.