Document Type
Article
Publication Date
3-28-2009
Abstract
An antichain A of a well-founded quasi-order Q is canonical if for every ideal F of Q, F has an infinite antichain if and only if F ∩ A is infinite. In this paper we characterize the obstructions to having a canonical antichain. As an application we show that, under the induced subgraph relation, the class of finite graphs does not have a canonical antichain. In contrast, this class does have a canonical antichain with respect to the subgraph relation. © 2008 Elsevier B.V. All rights reserved.
Publication Source (Journal or Book title)
Discrete Mathematics
First Page
1123
Last Page
1134
Recommended Citation
Ding, G. (2009). On canonical antichains. Discrete Mathematics, 309 (5), 1123-1134. https://doi.org/10.1016/j.disc.2007.12.018