Given a module M over an algebra Λ and a complete set of pairwise nonisomorphic indecomposable Λ-modules, the problem of determining the vector such that is studied. A general method of finding the vectors m(M) is presented (Corollary 2.1, Theorem 2.2 and Corollary 2.3). It is discussed and applied in practice for two classes of algebras: string algebras of finite representation type and hereditary algebras of type . In the second case detailed algorithms are given (Algorithms 4.5 and 5.5).
@article{bwmeta1.element.bwnjournal-article-doi-10_4064-cm107-2-4, author = {Piotr Dowbor and Andrzej Mr\'oz}, title = {The multiplicity problem for indecomposable decompositions of modules over a finite-dimensional algebra. Algorithms and a computer algebra approach}, journal = {Colloquium Mathematicae}, volume = {107}, year = {2007}, pages = {221-261}, zbl = {1149.16017}, language = {en}, url = {http://dml.mathdoc.fr/item/bwmeta1.element.bwnjournal-article-doi-10_4064-cm107-2-4} }
Piotr Dowbor; Andrzej Mróz. The multiplicity problem for indecomposable decompositions of modules over a finite-dimensional algebra. Algorithms and a computer algebra approach. Colloquium Mathematicae, Tome 107 (2007) pp. 221-261. http://gdmltest.u-ga.fr/item/bwmeta1.element.bwnjournal-article-doi-10_4064-cm107-2-4/