Compositionality of the MSO+U Logic
Logic in Computer Science
2020-05-07 v1
Abstract
We prove that the MSO+U logic is compositional in the following sense: whether an MSO+U formula holds in a tree T depends only on MSO+U-definable properties of the root of T and of subtrees of T starting directly below the root. Another kind of compositionality follows: every MSO+U formula whose all free variables range only over finite sets of nodes (in particular, whose all free variables are first-order) can be rewritten into an MSO formula having access to properties of subtrees definable by MSO+U sentences (without free variables).
Cite
@article{arxiv.2005.02384,
title = {Compositionality of the MSO+U Logic},
author = {Paweł Parys},
journal= {arXiv preprint arXiv:2005.02384},
year = {2020}
}
Comments
arXiv admin note: text overlap with arXiv:1810.04763