Great-circle tree thrackles
نویسندگان
چکیده
A thrackle is a graph drawing in which every pair of edges meets exactly once. Conway's Thrackle Conjecture states that the number cannot exceed its vertices. Cairns et al. (2015) [1] prove holds for great-circle thrackles drawn on sphere. They also posit can be restated to say as plane if and only it admits drawing. We demonstrate class thrackleable graphs excludes some trees. Thus informal conjecture from not equivalent Conjecture.
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ژورنال
عنوان ژورنال: Discrete Mathematics
سال: 2023
ISSN: ['1872-681X', '0012-365X']
DOI: https://doi.org/10.1016/j.disc.2022.113121