The scramble number
of a graph
is a graph invariant developed to aid in the study of gonality
of graphs. The scramble number is NP-hard to compute
(Echavarria et al. 2021).
The scramble number satisfies
where
is the edge connectivity and
is the vertex count of
.
The scramble number is the most powerful known lower bound on the gonality of a graph and satisfies
where
is the vertex connectivity,
is the edge connectivity,
is the treewidth,
and
is the gonality of
(Harp et al. 2020, Echavarria et al. 2021).
Unfortunately, the scramble number is not quite as well-behaved as treewidth (Echavarria et al. 2021).
The scramble number of the KC graph with
and
is
(Echavarria et al. 2021).