The rule labeling heuristic aims to establish confluence of (left-)linear#N#term rewrite systems via decreasing diagrams. We present a formalization of a#N#confluence criterion based on the interplay of relative termination and the#N#rule labeling in the theorem prover Isabelle. Moreover, we report on the#N#integration of this result into the certifier CeTA, facilitating the checking#N#of confluence certificates based on decreasing diagrams. The power of the#N#method is illustrated by an experimental evaluation on a (standard) collection#N#of confluence problems.
['Julian Nagele', 'Bertram Felgenhauer', 'Harald Zankl']
Certifying Confluence Proofs via Relative Termination and Rule Labeling