A cycle-path cover of a digraph D is a spanning subgraph made of disjoint cycles and paths. In order to count such covers by types we introduce the cyclepath indicator polynomial of D. We show that this polynomial can be obtained by a deletion-contraction recurrence relation. Then we study some spec
On the Cover Polynomial of a Digraph
β Scribed by F.R.K. Chung; R.L. Graham
- Publisher
- Elsevier Science
- Year
- 1995
- Tongue
- English
- Weight
- 511 KB
- Volume
- 65
- Category
- Article
- ISSN
- 0095-8956
No coin nor oath required. For personal study only.
π SIMILAR VOLUMES
Chung and Graham's cover polynomial is a generalization of the factorial rook polynomial in which the second variable keeps track of cycles. We factor the cover polynomial completely for Ferrers boards with either increasing or decreasing column heights. For column-permuted Ferrers boards, we find a
## Abstract We examine some properties of the 2βvariable greedoid polynomial __f__(__GΒ·,t,z__) when __G__ is the branching greedoid associated to a rooted graph or a rooted directed graph. For rooted digraphs, we show a factoring property of __f__(__GΒ·,t,z__) determines whether or not the rooted di
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