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.

A354496 Number of left-sided quantales on n elements, up to isomorphism. Also number of right-sided quantales on n elements, up to isomorphism.

Original entry on oeis.org

1, 2, 9, 60, 497, 4968, 58507, 807338, 13341730
Offset: 1

Views

Author

Arman Shamsgovara, Aug 03 2022

Keywords

Comments

For definition of quantale see A354493.
A quantale is left-sided if every element x satisfies T * x <= x, and right-sided if every element x satisfies x * T <= x. Here T denotes the top element of the underlying lattice.
Transposition of the semigroup table yields a bijection between left-sided and right-sided quantales, so this sequence counts either type.

References

  • P. Eklund, J. G. García, U. Höhle, and J. Kortelainen, (2018). Semigroups in complete lattices. In Developments in Mathematics (Vol. 54). Springer Cham.
  • K. I. Rosenthal, Quantales and their applications. Longman Scientific and Technical, 1990.
  • Arman Shamsgovara, A catalogue of every quantale of order up to 9 (abstract), LINZ2022, 39th Linz Seminar on Fuzzy Set Theory, Linz, Austria.

Crossrefs

Cf. A354493.