Title
Approximately Counting H-Colourings is \#\mathrm {BIS}-Hard
Abstract
We consider counting H-colourings from an input graph G to a target graph H. We show that for any fixed graph H without trivial components, this is as hard as the well-known problem #BIS, the problem of (approximately) counting independent sets in a bipartite graph. #BIS is a complete problem in an important complexity class for approximate counting, and is believed not to have an FPRAS. If this is so, then our result shows that for every graph H without trivial components, the H-colouring counting problem has no FPRAS. This problem was studied a decade ago by Goldberg, Kelk and Paterson. They were able to show that approximately sampling H-colourings is #BIS-hard, but it was not known how to get the result for approximate counting. Our solution builds on non-constructive ideas using the work of Lovasz. The full version is available at arxiv.org/abs/1502.01335. The theorem numbering here matches the full version.
Year
DOI
Venue
2016
10.1007/978-3-662-47672-7_43
Lecture Notes in Computer Science
Field
DocType
Volume
Complexity class,Numbering,Complete bipartite graph,Discrete mathematics,Graph,Combinatorics,Computer science,Bipartite graph,Counting problem,Sampling (statistics)
Journal
9134
Issue
ISSN
Citations 
3
0302-9743
0
PageRank 
References 
Authors
0.34
5
3
Name
Order
Citations
PageRank
andreas galanis16815.13
leslie ann goldberg21411125.20
mark jerrum32755564.62