English

Anti-Ramsey number of matchings in $r$-partite $r$-uniform hypergraphs

Combinatorics 2021-12-07 v2

Abstract

An edge-colored hypergraph is rainbow if all of its edges have different colors. Given two hypergraphs H\mathcal{H} and G\mathcal{G}, the anti-Ramsey number ar(G,H)ar(\mathcal{G}, \mathcal{H}) of H\mathcal{H} in G\mathcal{G} is the maximum number of colors needed to color the edges of G\mathcal{G} so that there does not exist a rainbow copy of H\mathcal{H}. Li et al. determined the anti-Ramsey number of kk-matchings in complete bipartite graphs. Jin and Zang showed the uniqueness of the extremal coloring. In this paper, as a generalization of these results, we determine the anti-Ramsey number arr(Kn1,,nr,Mk)ar_r(\mathcal{K}_{n_1,\ldots,n_r},M_k) of kk-matchings in complete rr-partite rr-uniform hypergraphs and show the uniqueness of the extremal coloring. Also, we show that Kk1,n2,,nr\mathcal{K}_{k-1,n_2,\ldots,n_r} is the unique extremal hypergraph for Tur\'{a}n number exr(Kn1,,nr,Mk)ex_r(\mathcal{K}_{n_1,\ldots,n_r},M_k) and show that arr(Kn1,,nr,ar_r(\mathcal{K}_{n_1,\ldots,n_r}, Mk)=exr(Kn1,,nr,Mk1)+1M_k)=ex_r(\mathcal{K}_{n_1,\ldots,n_r},M_{k-1})+1, which gives a multi-partite version result of \"Ozkahya and Young's conjecture.

Keywords

Cite

@article{arxiv.2109.05163,
  title  = {Anti-Ramsey number of matchings in $r$-partite $r$-uniform hypergraphs},
  author = {Yisai Xue and Erfang Shan and Liying Kang},
  journal= {arXiv preprint arXiv:2109.05163},
  year   = {2021}
}

Comments

12