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- Prikry forcing may add a Souslin tree June 12, 2016
- The reflection principle $R_2$ May 20, 2016
- Prolific Souslin trees March 17, 2016
- Generalizations of Martin’s Axiom and the well-met condition January 11, 2015
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stationary reflection Aronszajn tree Prevalent singular cardinals 05A17 Partition Relations Almost countably chromatic Stevo Todorcevic diamond star middle diamond projective Boolean algebra Forcing Microscopic Approach Slim tree Cardinal Invariants Parameterized proxy principle S-Space Fodor-type reflection Rock n' Roll square 20M14 approachability ideal Forcing Axioms Small forcing PFA weak diamond polarized partition relation Commutative cancellative semigroups Large Cardinals b-scale Constructible Universe Uniformization L-space sap Poset 11P99 Kurepa Hypothesis Almost-disjoint famiy stationary hitting Absoluteness Shelah's Strong Hypothesis Dushnik-Miller Whitehead Problem Nonspecial tree Distributive tree tensor product graph OCA Uniformly coherent Universal Sequences HOD free Boolean algebra Singular cardinals combinatorics Hereditarily Lindelöf space Erdos Cardinal Rainbow sets Antichain very good scale Prikry-type forcing Mandelbrot set ccc Club Guessing Martin's Axiom Axiom R Singular coﬁnality Erdos-Hajnal graphs Successor of Regular Cardinal Almost Souslin Foundations Sakurai's Bell inequality Chang's conjecture Hindman's Theorem Non-saturation square principles Minimal Walks Selective Ultrafilter Knaster Postprocessing function Hedetniemi's conjecture Ascent Path Successor of Singular Cardinal xbox coloring number Weakly compact cardinal Diamond Singular Density Cardinal function Cohen real Chromatic number Rado's conjecture Ostaszewski square Jonsson cardinal Fat stationary set weak square Square-Brackets Partition Relations incompactness Generalized Clubs PFA(S)[S] Fast club Reduced Power Coherent tree P-Ideal Dichotomy Souslin Tree 05D10 reflection principles

# Tag Archives: Erdos-Hajnal graphs

## The chromatic numbers of the Erdos-Hajnal graphs

Recall that a coloring $c:G\rightarrow\kappa$ of an (undirected) graph $(G,E)$ is said to be chromatic if $c(v_1)\neq c(v_2)$ whenever $\{v_1,v_2\}\in E$. Then, the chromatic number of a graph $(G,E)$ is the least cardinal $\kappa$ for which there exists a chromatic … Continue reading

Posted in Blog, Expository
Tagged Chromatic number, Erdos-Hajnal graphs, Rado's conjecture, reflection principles
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