English

Polynomial interpolation of partial functions in finite algebras with a Mal'cev term

Rings and Algebras 2026-04-01 v1

Abstract

We provide polynomial completeness results for finite algebras in congruence permutable varieties. In 2001, Idziak and S{\l}omczy{\'n}ska introduced the completeness concept of being \emph{polynomially rich}: a finite algebra is polynomially rich if every function preserving congruences and the Tame Congruence Theory labelling of prime quotients in the congruence lattice is a polynomial function of the algebra. We call a finite algebra \emph{strictly polynomially rich} if every partial congruence and type preserving function is a polynomial function, and we describe strictly polynomially rich algebras in congruence permutable varieties.

Keywords

Cite

@article{arxiv.2603.29589,
  title  = {Polynomial interpolation of partial functions in finite algebras with a Mal'cev term},
  author = {Erhard Aichinger and Mario Kapl and Bernardo Rossi},
  journal= {arXiv preprint arXiv:2603.29589},
  year   = {2026}
}