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arXiv · 2306.17607

Complete bipartite graphs without small rainbow stars

Weizhen Chen·Meng Ji·Yaping Mao·Meiqin Wei
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Abstract

The $k$-edge-colored bipartite Gallai-Ramsey number $\operatorname{bgr}_k(G:H)$ is defined as the minimum integer $n$ such that $n^2\geq k$ and for every $N\geq n$, every edge-coloring (using all $k$ colors) of complete bipartite graph $K_{N,N}$ contains a rainbow copy of $G$ or a monochromatic copy of $H$. In this paper, we first study the structural theorem on the complete bipartite graph $K_{n,n}$ with no rainbow copy of $K_{1,3}$. Next, we utilize the results to prove the exact values of $\operatorname{bgr}_{k}(P_4: H)$, $\operatorname{bgr}_{k}(P_5: H)$, $\operatorname{bgr}_{k}(K_{1,3}: H)$, where $H$ is a various union of cycles and paths and stars.

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Weizhen Chen, Meng Ji, Yaping Mao, Meiqin Wei. 2023-06-30. Complete bipartite graphs without small rainbow stars. https://arxiv.org/abs/2306.17607

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