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.

A383830 Number of Legendrian quandles of order n, up to isomorphism.

Original entry on oeis.org

1, 1, 2, 5, 15, 54, 240, 1306, 9477
Offset: 0

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Author

Luc Ta, May 11 2025

Keywords

Comments

A Legendrian quandle is a pair (X,u) where X is a quandle and u is an involutory automorphism of X such that u(yx)=y(u(x)); see Ta, "Generalized Legendrian...," Corollary 3.13.
a(n) is also the number of racks X such that the kink map X -> X defined by x -> x(x) is an involution; see Ta, "Equivalences of...," Theorem 1.1.

Crossrefs

Programs

  • GAP
    # See Ta, GitHub link