Star-critical Ramsey numbers for cycles versus K_4
نویسندگان
چکیده
منابع مشابه
Star-critical Ramsey numbers
The graph Ramsey number R(G,H) is the smallest integer r such that every 2-coloring of the edges of Kr contains either a red copy of G or a blue copy of H . We find the largest star that can be removed from Kr such that the underlying graph is still forced to have a red G or a blue H . Thus, we introduce the star-critical Ramsey number r∗(G,H) as the smallest integer k such that every 2-colorin...
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The star-critical Ramsey number r∗(H1,H2) is the smallest integer k such that every red/blue coloring of the edges of Kn −K1,n−k−1 contains either a red copy of H1 or a blue copy of H2, where n is the graph Ramsey number R(H1,H2). We study the cases of r∗(C4, Cn) and R(C4,Wn). In particular, we prove that r∗(C4, Cn) = 5 for all n > 4, obtain a general characterization of Ramsey-critical (C4,Wn)...
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ژورنال
عنوان ژورنال: Discussiones Mathematicae Graph Theory
سال: 2021
ISSN: 1234-3099,2083-5892
DOI: 10.7151/dmgt.2190