Leaps in the depth of compositions of irreducible morphisms
Abstract In this article, we give a family of examples of algebras, showing that for every $$n \ge 2$$ <mml:math xmlns:mml="http://www.w3.org/1998/Math/MathML"> <mml:mrow> <mml:mi>n</mml:mi> <mml:mo>≥</mml:mo> <mml:mn>2</mml:mn> </mml:mrow> </mml:math> and $$m \ge 0$$ <mml:math xmlns:mml="http://www.w3.org/1998/Math/MathML"> <mml:mrow> <mml:mi>m</mml:mi> <mml:mo>≥</mml:mo> <mml:mn>0</mml:mn> </mml:mrow> </mml:math> , there is an algebra displaying a path of n irreducible morphisms between indecomposable modules whose composite lies in the $$(n+m+3)$$ <mml:math xmlns:mml="http://www.w3.org/1998/Math/MathML"> <mml:mrow> <mml:mo>(</mml:mo> <mml:mi>n</mml:mi> <mml:mo>+</mml:mo> <mml:mi>m</mml:mi> <mml:mo>+</mml:mo> <mml:mn>3</mml:mn> <mml:mo>)</mml:mo> </mml:mrow> </mml:math> -th power of the radical, but not in the $$(n+m+4)$$ <mml:math xmlns:mml="http://www.w3.org/1998/Math/MathML"> <mml:mrow> <mml:mo>(</mml:mo> <mml:mi>n</mml:mi> <mml:mo>+</mml:mo> <mml:mi>m</mml:mi> <mml:mo>+</mml:mo> <mml:mn>4</mml:mn> <mml:mo>)</mml:mo> </mml:mrow> </mml:math> -th power. Such an algebra may be also supposed to be string and representation-finite.
Authors
- Flávio U. Coelho (ORCID: https://orcid.org/0000-0002-1292-621X)
- Viktor Chust (ORCID: https://orcid.org/0000-0003-4931-4222)
Institutions
- Universidade de São Paulo (BR)
Publication Details
- Journal
- Beiträge zur Algebra und Geometrie / Contributions to Algebra and Geometry
- Published
- 2026-06-19
- DOI
- https://doi.org/10.1007/s13366-026-00861-x
- Primary Topic
- Algebraic structures and combinatorial models
- Type
- article
- Field-Weighted Citation Impact
- 0.00
Funders
- Fundação de Amparo à Pesquisa do Estado de São Paulo
- Coordenação de Aperfeiçoamento de Pessoal de Nível Superior
- Conselho Nacional de Desenvolvimento Científico e Tecnológico