Gap Embedding for Well-Quasi-Orderings
β Scribed by Nachum Dershowitz; Iddo Tzameret
- Publisher
- Elsevier Science
- Year
- 2003
- Tongue
- English
- Weight
- 683 KB
- Volume
- 84
- Category
- Article
- ISSN
- 1571-0661
No coin nor oath required. For personal study only.
π SIMILAR VOLUMES
The constructions and proofs of this paper are to be understood as taking place in some kind of basic set theory or type theory, based on intuitionistic logic. \lie assunie a set N of natural numbers, satisfying HEYTING'S arithmetic (with full induction) ; we can form products of sets, and subsets o
## Abstract Let π΄ be a class of graphs and let βͺ― be the subgraph or the induced subgraph relation. We call βͺ― an __ideal__ (with respect to βͺ―) if βͺ― implies that βͺ―. In this paper, we study the ideals that are wellβquasiordered by βͺ―. The following are our main results. If βͺ― is the subgraph relation, w
Let (X.U) be a quasi-uniform space and M, its Hausdorff quasi-uniformity defined on the collection PO(X) of all nonempty subsets of X. We show that (PO(X). U,) is compact if and only if (X.U) is compact and (X,,U-'IX,,) is hereditarily precompact where X,,, = {y E X: y is minimal in the (specializa