Geodesic
Remarks on 15-vertex (3,3)-ramsey graphs not containing K₅
Discussiones Mathematicae. Graph Theory, Tome 16 (1996) no. 2, pp. 173-179.

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The paper gives an account of previous and recent attempts to determine the order of a smallest graph not containing K₅ and such that every 2-coloring of its edges results in a monochromatic triangle. A new 14-vertex K₄-free graph with the same Ramsey property in the vertex coloring case is found. This yields a new construction of one of the only two known 15-vertex (3,3)-Ramsey graphs not containing K₅.
Keywords: Folkman numbers, Kₙ-free graphs, extremal graph theory, generalized Ramsey theory 
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Urbański, Sebastian. Remarks on 15-vertex (3,3)-ramsey graphs not containing K₅. Discussiones Mathematicae. Graph Theory, Tome 16 (1996) no. 2, pp. 173-179. http://geodesic.mathdoc.fr/item/DMGT_1996_16_2_a7/

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