Turán's problem and Ramsey numbers for trees

Zhi-Hong Sun; Lin-Lin Wang; Yi-Li Wu

Colloquium Mathematicae (2015)

  • Volume: 139, Issue: 2, page 273-298
  • ISSN: 0010-1354

Abstract

top
Let T¹ₙ = (V,E₁) and T²ₙ = (V,E₂) be the trees on n vertices with V = v , v , . . . , v n - 1 , E = v v , . . . , v v n - 3 , v n - 4 v n - 2 , v n - 3 v n - 1 and E = v v , . . . , v v n - 3 , v n - 3 v n - 2 , v n - 3 v n - 1 . For p ≥ n ≥ 5 we obtain explicit formulas for ex(p;T¹ₙ) and ex(p;T²ₙ), where ex(p;L) denotes the maximal number of edges in a graph of order p not containing L as a subgraph. Let r(G₁,G₂) be the Ramsey number of the two graphs G₁ and G₂. We also obtain some explicit formulas for r ( T , T i ) , where i ∈ 1,2 and Tₘ is a tree on m vertices with Δ(Tₘ) ≤ m - 3.

How to cite

top

Zhi-Hong Sun, Lin-Lin Wang, and Yi-Li Wu. "Turán's problem and Ramsey numbers for trees." Colloquium Mathematicae 139.2 (2015): 273-298. <http://eudml.org/doc/284134>.

@article{Zhi2015,
abstract = {Let T¹ₙ = (V,E₁) and T²ₙ = (V,E₂) be the trees on n vertices with $V = \{v₀,v₁,...,v_\{n-1\}\}$, $E₁ = \{v₀v₁,..., v₀v_\{n-3\},v_\{n-4\}v_\{n-2\},v_\{n-3\}v_\{n-1\}\}$ and $E₂ = \{v₀v₁,..., v₀v_\{n-3\},v_\{n-3\}v_\{n-2\},v_\{n-3\}v_\{n-1\}\}$. For p ≥ n ≥ 5 we obtain explicit formulas for ex(p;T¹ₙ) and ex(p;T²ₙ), where ex(p;L) denotes the maximal number of edges in a graph of order p not containing L as a subgraph. Let r(G₁,G₂) be the Ramsey number of the two graphs G₁ and G₂. We also obtain some explicit formulas for $r(Tₘ,Tₙ^i)$, where i ∈ 1,2 and Tₘ is a tree on m vertices with Δ(Tₘ) ≤ m - 3.},
author = {Zhi-Hong Sun, Lin-Lin Wang, Yi-Li Wu},
journal = {Colloquium Mathematicae},
keywords = {Ramsey number; Turán’s problem},
language = {eng},
number = {2},
pages = {273-298},
title = {Turán's problem and Ramsey numbers for trees},
url = {http://eudml.org/doc/284134},
volume = {139},
year = {2015},
}

TY - JOUR
AU - Zhi-Hong Sun
AU - Lin-Lin Wang
AU - Yi-Li Wu
TI - Turán's problem and Ramsey numbers for trees
JO - Colloquium Mathematicae
PY - 2015
VL - 139
IS - 2
SP - 273
EP - 298
AB - Let T¹ₙ = (V,E₁) and T²ₙ = (V,E₂) be the trees on n vertices with $V = {v₀,v₁,...,v_{n-1}}$, $E₁ = {v₀v₁,..., v₀v_{n-3},v_{n-4}v_{n-2},v_{n-3}v_{n-1}}$ and $E₂ = {v₀v₁,..., v₀v_{n-3},v_{n-3}v_{n-2},v_{n-3}v_{n-1}}$. For p ≥ n ≥ 5 we obtain explicit formulas for ex(p;T¹ₙ) and ex(p;T²ₙ), where ex(p;L) denotes the maximal number of edges in a graph of order p not containing L as a subgraph. Let r(G₁,G₂) be the Ramsey number of the two graphs G₁ and G₂. We also obtain some explicit formulas for $r(Tₘ,Tₙ^i)$, where i ∈ 1,2 and Tₘ is a tree on m vertices with Δ(Tₘ) ≤ m - 3.
LA - eng
KW - Ramsey number; Turán’s problem
UR - http://eudml.org/doc/284134
ER -

NotesEmbed ?

top

You must be logged in to post comments.

To embed these notes on your page include the following JavaScript code on your page where you want the notes to appear.

Only the controls for the widget will be shown in your chosen language. Notes will be shown in their authored language.

Tells the widget how many notes to show per page. You can cycle through additional notes using the next and previous controls.

    
                

Note: Best practice suggests putting the JavaScript code just before the closing </body> tag.