# Great-circle Tree Thrackles

@inproceedings{Collins2021GreatcircleTT, title={Great-circle Tree Thrackles}, author={Karen L. Collins and Cleo Roberts}, year={2021} }

A thrackle is a graph drawing in which every pair of edges meets exactly once. Conway’s Thrackle Conjecture states that the number of edges of a thrackle cannot exceed the number of its vertices. Cairns et al (2015) prove that the Thrackle Conjecture holds for great-circle thrackles drawn on the sphere. They also posit that Conway’s Thrackle Conjecture can be restated to say that a graph can be drawn as a thrackle drawing in the plane if and only if it admits a great-circle thrackle drawing. We…

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## References

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