A strongly Hamiltonian-laceable graph is a Hamilton-laceable graph on vertices with two bipartition
classes of equal size such that every pair of distinct vertices
in the same bipartition class can be joined by a
path of length
(Hsieh et al. 2000).
The longest path between distinct vertices therefore has length for endpoints in different bipartition
classes and
for endpoints in the same class. These lengths are maximal
because a path visits each vertex
at most once and alternates between the bipartition classes.
There are unordered pairs of vertices
in different bipartition classes and
pairs in the same class. Consequently, the detour
index of a strongly Hamiltonian-laceable graph
is
The permutation star graph (Hsieh et al. 2000) and the Bruhat
graph
(Araki and Kikuchi 2007) are strongly Hamiltonian-laceable
for
.