Combinatorics/Geometry
Gallai triangles in configurations of lines in the projective plane
[Triangles de Gallai dans les configurations de droites du plan projective]
Comptes Rendus. Mathématique, Tome 354 (2016) no. 6, pp. 551-554.

La note répond négativement à une question posée par Paul Erdős concernant l'existence de triangles de Gallai dans les configurations de d droites réelles du plan projective, dans la situation où d>3 et où au plus trois droites concourent en chaque sommet.

A question by Paul Erdős about the existence of Gallai triangles in arrangements of d real lines in the projective plane, with no more than three lines incident to each vertex, is answered in the negative for all d higher than three.

Reçu le :
Accepté le :
Publié le :
DOI : 10.1016/j.crma.2016.03.003
Escudero, Juan García 1

1 Universidad de Oviedo, Facultad de Ciencias, 33007 Oviedo, Spain
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Escudero, Juan García. Gallai triangles in configurations of lines in the projective plane. Comptes Rendus. Mathématique, Tome 354 (2016) no. 6, pp. 551-554. doi : 10.1016/j.crma.2016.03.003. http://www.numdam.org/articles/10.1016/j.crma.2016.03.003/

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