A Delsarte clique is a clique for which the inequality in the Delsarte bound for distance-regular graph becomes an equality (Koolen et al. 2023).
A distance-regular graph 
that contains a set of Delsarte cliques 
such that every edge of 
lies in a unique member of 
is known as a geometric distance-regular graph (Koolen et al. 2023).
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15 Nov 2023.