96 citations · 283 across the 48 of their papers we have counts for
51 papers
Bounding the parameter of a distance-regular graph with classical parameters
Chenhui Lv, Jack H. Koolen
Let be a distance-regular graph with classical parameters satisfying and . Let . In 1999, K. Metsch showed that ther…
Characterizations of amorphic schemes and fusions of pairs
Edwin R. van Dam, Jack H. Koolen, Yanzhen Xiong
An association scheme is called amorphic if every possible fusion of relations gives rise to a fusion scheme. We call a pair of relations fusing if fusing that pair gives rise to a…
Distance-regular graphs with a few -distance eigenvalues
Mamoon Abdullah, Brhane Gebremichel, Sakander Hayat +1
In this paper we study when the -distance matrix of a distance-regular graph has few distinct eigenvalues. We mainly concentrate on diameter 3.
On the (non-)existence of tight distance-regular graphs: a local approach
Jack H. Koolen, Jae-Ho Lee, Shuang-Dong Li +3
Let denote a distance-regular graph with diameter . Jurišić and Vidali conjectured that if is tight with classical parameters , , then is n…
A New Feasibility Condition for the AT4 Family
Zheng-Jiang Xia, Jae-Ho Lee, Jack H. Koolen
Let be an antipodal distance-regular graph with diameter and eigenvalues . Then is tight in the sense of Jurišić, Koolen, and Terwilliger [12] when…
An infinite class of Neumaier graphs and non-existence results
Aida Abiad, Wouter Castryck, Maarten De Boeck +2
A Neumaier graph is a non-complete edge-regular graph containing a regular clique. A Neumaier graph that is not strongly regular is called a strictly Neumaier graph. In this work w…