AI and the World's Hard Problems · Theoretical computer science · arXiv · 2026-10-19
LLM-Assisted Bi-Approximate CHC Solving
Constrained Horn clause solvers often fail to find deep counterexamples that need long chains of rule unfolding. The authors have an LLM propose Derivation Power Under-approximations, which are solver-checked under-approximations of multi-step derivations, and combine them with invariant generation in the HornCraft framework. On 260 benchmarks left unresolved by a 30-minute Spacer run, HornCraft certified verdicts for 228, including 42 unsafe instances compared with 22 when DPUs are disabled.