A regular nonempty graph $\Gamma$ is called edge regular, whenever there exists a nonegative integer $\lambda_{\Gamma}$, such that any two adjacent vertices of $\Gamma$ have precisely $\lambda_{\Gamma}$ common neighbours. An edge regular graph $\Gamma$ with at least one pair of vertices at distance 2 is called amply regular, whenever there exists a nonegative integer $\mu_{\Gamma}$, such that any two vertices at distance 2 have precisely $\mu_{\Gamma}$ common neighbours. In this paper we classify edge regular graphs, which can be obtained as a strong product, or a lexicographic product, or a deleted lexicographic product, or a co-normal product of two graphs. As a corollary we determine which of these graphs are amply regular.
@article{10_37236_2817,
author = {Bo\v{s}tjan Frelih and \v{S}tefko Miklavi\v{c}},
title = {Edge regular graph products},
journal = {The electronic journal of combinatorics},
year = {2013},
volume = {20},
number = {1},
doi = {10.37236/2817},
zbl = {1266.05130},
url = {http://geodesic.mathdoc.fr/articles/10.37236/2817/}
}
TY - JOUR
AU - Boštjan Frelih
AU - Štefko Miklavič
TI - Edge regular graph products
JO - The electronic journal of combinatorics
PY - 2013
VL - 20
IS - 1
UR - http://geodesic.mathdoc.fr/articles/10.37236/2817/
DO - 10.37236/2817
ID - 10_37236_2817
ER -