The planar Ramsey number PR(K4-e, K5)
نویسندگان
چکیده
The planar Ramsey number PR (H1, H2) is the smallest integer n such that any planar graph on n vertices contains a copy of H1 or its complement contains a copy of H2. It is known that the Ramsey number R(K4 − e, K6) = 21, and the planar Ramsey numbers PR(K4 − e, Kl) for l ≤ 5 are known. In this paper, we give the lower bounds on PR (K4 − e, Kl) and determine the exact value of PR (K4 − e, K6).
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ورودعنوان ژورنال:
- Discrete Mathematics
دوره 307 شماره
صفحات -
تاریخ انتشار 2007