2 papers
math.CO2017
A diagram associated with the subconstituent algebra of a distance-regular graph
Supalak Sumalroj
In this paper we consider a distance-regular graph . Fix a vertex of and consider the corresponding subconstituent algebra . The algebra is the -algeb…
math.CO2017
A characterization of -polynomial distance-regular graphs using the intersection numbers
Supalak Sumalroj
We consider a primitive distance-regular graph with diameter at least . We use the intersection numbers of to find a positive semidefinite matrix with integer entrie…