Configured network: yes after 19 square candidates.
Desired/crossed boundary determinants: -3 0
Complete 20-vertex switch replay: {'vertices': 20, 'arcs': 29, 'simple_port_paths': 77, 'control_pairs': 3, 'control_pair_checks': 3, 'residual_mode_counts': {'(2, 6)': 2, '(3, 7)': 1}, 'all_three_properties': True, 'scope': 'Complete Python simple-path enumeration on the fixed 20-vertex gadget; independent finite replay, not a Lean kernel run.'}
Compiled formula: {'clauses': ((1,), (-1, 2)), 'variables': 2, 'occurrences': 3, 'vertices': 106, 'arcs': 157, 'source_entities': 157, 'source_reactions': 104, 'max_stoichiometry': 2, 'assignment_search': {'status': 'sat', 'assignment': (True, True)}, 'certificate_verified': True, 'square_size': 80, 'integer_flow_bits': 9}
Certificates establish literal structural productivity and PAC existence. They do not prescribe concentrations, kinetics or conserved elemental chemistry. Exhaustive NO and budget-limited UNKNOWN are distinct. Lean and machine-time proofs are not rerun.