Year: 2019
Type: article
Abstract: Finding the set of leaves for an unbounded tree is a nontrivial process in both the Weihrauch and reverse mathematics settings. Despite this, many combinatorial principles for trees are equivalent to their restrictions to trees with leaf sets. For example, let WFˆ denote the problem of choosing whi ch trees in a sequence are well-founded, and let PK denote the problem of finding the perfect kernel of a tree. Let WFˆL and PKL denote the restrictions of these principles to trees with leaf sets. Then WFˆ, WFˆL, PK, and PKL are all equivalent to Π11–CA0 over RCA0, and all strongly Weihrauch equivalent.
Source: Computability
DOI: 10.3233/com-180243
Author: Jeffry L. Hirst
Institution: Appalachian State University
Language: English
Subfield: Computational Theory and Mathematics
Field: Computer Science
Domain: Physical Sciences
Open Access status: green
OpenAlex ID: W2906355379