Title
Complexity of the cover polynomial
Abstract
The cover polynomial introduced by Chung and Graham is a two-variate graph polynomial for directed graphs. It counts the (weighted) number of ways to cover a graph with disjoint directed cycles and paths, it is an interpolation between determinant and permanent, and it is believed to be a directed analogue of the Tutte polynomial. Jaeger, Vertigan, and Welsh showed that the Tutte polynomial is #Phard to evaluate at all but a few special points and curves. It turns out that the same holds for the cover polynomial: We prove that, in almost the whole plane, the problem of evaluating the cover polynomial is #Phard under polynomial-time Turing reductions, while only three points are easy. Our construction uses a gadget which is easier to analyze and more general than the XOR-gadget used by Valiant in his proof that the permanent is #P-complete.
Year
DOI
Venue
2007
10.1007/978-3-540-73420-8_69
ICALP
Keywords
Field
DocType
whole plane,polynomial-time turing reduction,tutte polynomial,two-variate graph polynomial,special point,cover polynomial,directed graph,polynomial time
Discrete mathematics,Characteristic polynomial,Stable polynomial,Combinatorics,Edge cover,Tutte polynomial,Monic polynomial,Reciprocal polynomial,Matrix polynomial,Chromatic polynomial,Mathematics
Conference
Volume
ISSN
ISBN
4596
0302-9743
3-540-73419-8
Citations 
PageRank 
References 
18
0.82
8
Authors
2
Name
Order
Citations
PageRank
Markus Bläser132634.03
Holger Dell222016.74