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A143660 Erroneous version of A170946. 0
2, 15, 20, 107 (list; graph; refs; listen; history; text; internal format)
The theory of dessins d'enfants was initiated by A. Grothendieck. "In this work, using the matrix model approach... we listed all the dessins d'enfants with no more than 4 edges. There are two 1-edge dessins, both of them are of genus zero, fifteen 2-edge dessins, among them only one is of genus 1, twenty 3-edge dessins: 14 sperical [sic] and 6 of genus 1 and one hundred seven 4-edge dessins: 57 spherical dessins, 46 dessins of genus 1 and 4 dessins of genus 2. The total number of dessins is 134."
Note: The fifteen for n=2 is a typo, it should be 5. The sum: 2+5+20+107=134 adds up if we replace fifteen by 5, and moreover, the section on 2-edge dessins lists all 5 (not fifteen) dessins. The correct version of this sequence is given by A170946. - Mark van Hoeij, Jan 23 2011
N. M. Adrianov, N. Ya. Amburg, V. A. Dremov, Yu. A. Levitskaya, E. M. Kreines, Yu. Yu. Kochetkov, V. F. Nasretdinova and G. B. Shabat, Catalog of dessins d'enfants with <= 4 edges, arXiv:0710.2658 [math.AG], 2007.
Sequence in context: A091791 A281660 A244324 * A198391 A278889 A075722

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Last modified October 1 02:24 EDT 2023. Contains 365812 sequences. (Running on oeis4.)