Title:
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A note on the size Ramsey numbers for matchings versus cycles (English) |
Author:
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Baskoro, Edy Tri |
Author:
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Vetrík, Tomáš |
Language:
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English |
Journal:
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Mathematica Bohemica |
ISSN:
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0862-7959 (print) |
ISSN:
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2464-7136 (online) |
Volume:
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146 |
Issue:
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2 |
Year:
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2021 |
Pages:
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229-234 |
Summary lang:
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English |
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Category:
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math |
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Summary:
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For graphs $G$, $F_1$, $F_2$, we write $G \rightarrow (F_1, F_2)$ if for every red-blue colouring of the edge set of $G$ we have a red copy of $F_1$ or a blue copy of $F_2$ in $G$. The size Ramsey number $\hat {r}(F_1, F_2)$ is the minimum number of edges of a graph $G$ such that $G \rightarrow (F_1, F_2)$. Erdős and Faudree proved that for the cycle $C_n$ of length $n$ and for $t \ge 2$ matchings $tK_2$, the size Ramsey number $\hat {r} (tK_2, C_n) < n + (4t+3) \sqrt {n}$. We improve their upper bound for $t = 2$ and $t=3$ by showing that $\hat {r} (2K_2, C_n) \le n + 2 \sqrt {3n} + 9$ for $n \ge 12$ and $\hat {r} (3K_2, C_n) < n + 6 \sqrt {n} + 9$ for $n \ge 25$. (English) |
Keyword:
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size Ramsey number |
Keyword:
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matching |
Keyword:
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cycle |
MSC:
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05C35 |
MSC:
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05C55 |
DOI:
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10.21136/MB.2020.0174-18 |
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Date available:
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2021-05-20T13:56:06Z |
Last updated:
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2021-06-07 |
Stable URL:
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http://hdl.handle.net/10338.dmlcz/148934 |
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Reference:
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Reference:
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[2] Erdős, P., Faudree, R. J.: Size Ramsey numbers involving matchings.Finite and Infinite Sets. Vol. I, II (Eger, 1981) Colloquia Mathematica Societatis János Bolyai 37. János Bolyai Mathematical Society, Budapest; North-Holland, Amsterdam (1984), 247-264 A. Hajnal et al. Zbl 0563.05043, MR 0818238, 10.1016/B978-0-444-86893-0.50019-X |
Reference:
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[3] Erdős, P., Faudree, R. J., Rousseau, C. C., Schelp, R. H.: The size Ramsey number.Period. Math. Hung. 9 (1978), 145-161. Zbl 0331.05122, MR 0479691, 10.1007/BF02018930 |
Reference:
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[4] Faudree, R. J., Sheehan, J.: Size Ramsey numbers for small-order graphs.J. Graph Theory 7 (1983), 53-55. Zbl 0505.05043, MR 0693020, 10.1002/jgt.3190070107 |
Reference:
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[5] Ke, X.: The size Ramsey number of trees with bounded degree.Random Struct. Algorithms 4 (1993), 85-97. Zbl 0778.05060, MR 1192528, 10.1002/rsa.3240040106 |
Reference:
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[6] Lortz, R., Mengersen, I.: Size Ramsey results for paths versus stars.Australas. J. Comb. 18 (1998), 3-12. Zbl 0914.05053, MR 1658352 |
Reference:
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[7] Perondi, P. H., Carmelo, E. L. Monte: Set and size multipartite Ramsey numbers for stars.Discrete Appl. Math. 250 (2018), 368-372. Zbl 1398.05131, MR 3868682, 10.1016/j.dam.2018.05.016 |
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