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,
one of them being the triangular graph of order
8. The other three such graphs are known as the Chang graphs, illustrated above.
The Chang graphs are also cospectral with the
triangular graph 
, all having graph spectrum 
, meaning none of the
these is determined by spectrum.
but are not distance-transitive.
They are pancyclic.
"Chang", n
] for 
, 2, 3.
, 
, 
, and 
." Sci. Record Peking Math. 4,
12-18, 1960.DistanceRegular.org. "Chang Graphs (3 Graphs)."