The Intercalation Enumeration: A 50,388-Placement Exhaustive Test of the Window Property Under Observational Intercalation

Version 3 adds the two scripts establishing the claims stated below: verify_enumeration.py (combinatorial layer, 57 of 50,388 placements admissible) and intercalation_57_corridor_verify.py (corridor layer, 9,690,000 evaluations across all 57 admissible patterns, zero exceptions). Versions 1–2 stated these results without attached code. The deposited papers in this series establish their headline results on the fixed rabbinic Hebrew calendar and report robustness across an 85,000-case convention battery with zero corridor exceptions. One objection remains open in the deposited record: the fixed calendar’s Metonic intercalation pattern is a fourth-century codification, and an observational calendar governed by the aviv could in principle have followed a different pattern of leap years. This supplement closes that gap at the pattern level. All 50,388 possible placements of seven leap years within a nineteen-year cycle are enumerated. Exactly 57 placements survive the agronomic admissibility constraint that leap years be separated by gaps of two or three years. Every one of the 57 admissible patterns satisfies the window property of the principal papers, with zero exceptions. The corridor result therefore does not depend on the specific intercalation pattern codified in the fixed calendar. Any aviv-plausible intercalation schedule produces it.