Invalid proofs on incidence coloring
نویسندگان
چکیده
منابع مشابه
Easier proofs of coloring theorems
We present a simpler proof of the known theorem that a fixed-point free homeomorphism on an n-dimensional paracompact space can be colored with n+ 3 colors. 1999 Elsevier Science B.V. All rights reserved.
متن کاملOn incidence coloring for some cubic graphs
In 1993, Brualdi and Massey conjectured that every graph can be incidence colored with ∆+2 colors, where ∆ is the maximum degree of a graph. Although this conjecture was solved in the negative by an example in [1], it might hold for some special classes of graphs. In this paper, we consider graphs with maximum degree ∆ = 3 and show that the conjecture holds for cubic Hamiltonian graphs and some...
متن کاملShort proofs of coloring theorems on planar graphs
A recent lower bound on the number of edges in a k-critical nvertex graph by Kostochka and Yancey yields a half-page proof of the celebrated Grötzsch Theorem that every planar triangle-free graph is 3-colorable. In this paper we use the same bound to give short proofs of other known theorems on 3-coloring of planar graphs, among whose is the Grünbaum-Aksenov Theorem that every planar with at mo...
متن کاملGeneralized Kneser Coloring Theorems with Combinatorial Proofs
The Kneser conjecture (1955) was proved by Lovász (1978) using the Borsuk-Ulam theorem; all subsequent proofs, extensions and generalizations also relied on Algebraic Topology results, namely the Borsuk-Ulam theorem and its extensions. Only in 2000, Matoušek provided the first combinatorial proof of the Kneser conjecture. Here we provide a hypergraph coloring theorem, with a combinatorial proof...
متن کاملOn incidence coloring and star arboricity of graphs
In this note we show that the concept of incidence coloring introduced in [BM] is a special case of directed star arboricity, introduced in [AA]. A conjecture in [BM] concerning asmyptotics of the incidence coloring number is solved in the negative following an example in [AA]. We generalize Theorem 2.1 of [AMR] concerning the star arboricity of graphs to the directed case by a slight modificat...
متن کاملذخیره در منابع من
با ذخیره ی این منبع در منابع من، دسترسی به آن را برای استفاده های بعدی آسان تر کنید
ژورنال
عنوان ژورنال: Discrete Mathematics
سال: 2008
ISSN: 0012-365X
DOI: 10.1016/j.disc.2007.11.030