cp's OEIS Frontend

This is a front-end for the Online Encyclopedia of Integer Sequences, made by Christian Perfect. The idea is to provide OEIS entries in non-ancient HTML, and then to think about how they're presented visually. The source code is on GitHub.

User: Paawan Jethva

Paawan Jethva's wiki page.

Paawan Jethva has authored 1 sequences.

A380453 Number of dessins d'enfants D(n,g) with n edges of genus g, read by rows.

Original entry on oeis.org

1, 3, 6, 1, 20, 6, 60, 33, 4, 291, 285, 48, 1310, 2115, 708, 30, 6975, 16533, 9807, 1155, 37746, 126501, 119436, 29910, 900, 215602, 972441, 1355400, 601364, 58032, 1262874, 7451679, 14561360, 10260804, 2112300, 54990, 7611156, 57167260, 150429819, 156469887, 57017238, 4764654
Offset: 1

Author

Paawan Jethva, Jun 22 2025

Keywords

Comments

Note that Sum_{g>=0} D(n,g) gives A057005 which is the number of dessins d'enfants with n edges (as one would hope).
We get a new genus every two edges.
n=7 is the first time we have more dessins of genus 1 than genus 0.

Examples

			Triangle D(n,g) begins:
   n\g    0      1      2      3      4      ...
   1      1
   2      3
   3      6      1
   4      20     6
   5      60     33     4
   6      291    285    48
   7      1310   2115   708    30
   8      6975   16533  9807   1155
   9      37746  126501 119436 29910  900
   ...
		

Crossrefs

Cf. A057005.
Columns: A090371, A118094, A214819, A214820, A356694. A321710 is the rooted version.

Extensions

Rows 10-11 from Andrei Zabolotskii, Jun 28 2025