کد مقاله کد نشریه سال انتشار مقاله انگلیسی نسخه تمام متن
4652600 1632594 2011 6 صفحه PDF دانلود رایگان
عنوان انگلیسی مقاله ISI
Oriented coloring of triangle-free planar graphs and 2-outerplanar graphs
موضوعات مرتبط
مهندسی و علوم پایه ریاضیات ریاضیات گسسته و ترکیبات
پیش نمایش صفحه اول مقاله
Oriented coloring of triangle-free planar graphs and 2-outerplanar graphs
چکیده انگلیسی

A graph is 2-outerplanar if it has a planar embedding such that the subgraph obtained by removing the vertices of the external face is outerplanar (i.e. with all its vertices on the external face). An oriented k-coloring of an oriented graph G is a homomorphism from G to an oriented graph H of order k. We prove that (1) every oriented triangle-free planar graph has an oriented chromatic number at most 40, and (2) every oriented 2-outerplanar graph has an oriented chromatic number at most 40, that improves the previous known bounds of 47 and 67, respectively.

ناشر
Database: Elsevier - ScienceDirect (ساینس دایرکت)
Journal: Electronic Notes in Discrete Mathematics - Volume 37, 1 August 2011, Pages 123-128