کد مقاله کد نشریه سال انتشار مقاله انگلیسی نسخه تمام متن
4648904 1342435 2010 5 صفحه PDF دانلود رایگان
عنوان انگلیسی مقاله ISI
A new bound for a particular case of the Caccetta–Häggkvist conjecture
موضوعات مرتبط
مهندسی و علوم پایه ریاضیات ریاضیات گسسته و ترکیبات
پیش نمایش صفحه اول مقاله
A new bound for a particular case of the Caccetta–Häggkvist conjecture
چکیده انگلیسی

In a recent paper, Hladký et al. (2009) (see [8]) proved that for α≥0.3465α≥0.3465, any digraph DD of order nn with minimum out-degree at least αnαn contains a cycle of length at most 3. Hamburger et al. (2007) (see [7]) proved that for β≥0.34564β≥0.34564, any digraph DD of order nn with both minimum out-degree and minimum in-degree at least βnβn contains a cycle of length at most 33. In this paper, by using the first result, we slightly improve the second bound. Namely, we prove that for β≥0.343545β≥0.343545, any digraph DD of order nn with both minimum out-degree and minimum in-degree at least βnβn contains a cycle of length at most 3. This result will be in fact a consequence of a quite general result.

ناشر
Database: Elsevier - ScienceDirect (ساینس دایرکت)
Journal: Discrete Mathematics - Volume 310, Issue 23, 6 December 2010, Pages 3368–3372
نویسندگان
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