A new lower bound on graph gonality

نویسندگان

چکیده

We define a new graph invariant called the scramble number. show that number of is lower bound for gonality and an upper treewidth. Unlike treewidth, not minor monotone, but it subgraph monotone under subdivision. compute several families graphs which these invariants are strictly greater than

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ژورنال

عنوان ژورنال: Discrete Applied Mathematics

سال: 2022

ISSN: ['1872-6771', '0166-218X']

DOI: https://doi.org/10.1016/j.dam.2021.11.003