Almost -rainbow edge-colorings of some small graphs
نویسندگان
چکیده
Let f(n, p, q) be the minimum number of colors necessary to color the edges of Kn so that every Kp is at least q-colored. We improve current bounds on these nearly “anti-Ramsey” numbers, first studied by Erdős and Gyárfás. We show that f(n, 5, 9) ≥ 7 4 n− 3, slightly improving the bound of Axenovich. We make small improvements on bounds of Erdős and Gyárfás by showing 5 6 n+1 ≤ f(n, 4, 5) and for all even n 6≡ 1(mod 3), f(n, 4, 5) ≤ n− 1. For a complete bipartite graphG = Kn,n, we show an n-color construction to color the edges of G so that every C4 ⊆ G is colored by at least three colors. This improves the best known upper bound of Axenovich, Füredi, and Mubayi.
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عنوان ژورنال:
- Discussiones Mathematicae Graph Theory
دوره 33 شماره
صفحات -
تاریخ انتشار 2013