J 2009

Projective, affine, and abelian colorings of cubic graphs

KRÁĽ, Daniel; E MACAJOVA; O PANGRAC; A RASPAUD; JS SERENI et. al.

Základní údaje

Originální název

Projective, affine, and abelian colorings of cubic graphs

Autoři

KRÁĽ, Daniel; E MACAJOVA; O PANGRAC; A RASPAUD; JS SERENI a M SKOVIERA

Vydání

European Journal of Combinatorics, LONDON, ACADEMIC PRESS LTD- ELSEVIER SCIENCE LTD, 2009, 0195-6698

Další údaje

Jazyk

angličtina

Typ výsledku

Článek v odborném periodiku

Utajení

není předmětem státního či obchodního tajemství

Impakt faktor

Impact factor: 0.822

UT WoS

000260960100008
Změněno: 6. 11. 2020 10:15, Mgr. Darina Boukalová

Anotace

V originále

We develop an idea of a local 3-edge-coloring of a cubic graph, a generalization of the usual 3-edge-coloring. We allow for an unlimited number of colors but require that the colors of two edges meeting at a vertex always determine the same third color. Local 3-edge-colorings are described in terms of colorings by points of a partial Steiner triple system such that the colors meeting at each vertex form a triple of the system. An important place in our investigation is held by the two smallest non-trivial Steiner triple systems, the Fano plane PG(2, 2) and the affine plane AG(2, 3). For i = 4, 5, and 6 we identify certain configurations F-i and A(i) of i lines of the Fano plane and the affine plane, respectively, and prove a theorem saying that a cubic graph admits an F-i-coloring if and only if it admits an A(i)-coloring. Among consequences of this is the result of Holroyd and Skoviera [F. Holroyd, M. Skoviera, Colouring of cubic graphs by Steiner triple systems, J. Combin. Theory Set. B 91 (2004) 57-66] that the edges of every bridgeless cubic graph can be colored by using points and blocks of any non-trivial Steiner triple system S.