Acyclic digraphs giving rise to complete intersections (Q2002592)

A digraph is \(2\)-connected if the removal of any vertex leaves a connected digraph. An acyclic digraph is called a CI-digraph if a certain affine semigroup ring defined by it is a complete intersection. In the paper under review the author proves that a \(2\)-connected CI-digraph with cycle space of dimension at least \(2\) can be decomposed into two sub-CI-digraphs that are glued along a directed path. This in particular shows that CI-digraphs can be easily recognized.