King and Two Knights on Cylindrical Chessboards: Complete Enumeration of Checkmates and Computed Non-Forceability (v2.2 deposit: paper, proof scripts, verification certificate)

Complete enumeration of K+2N vs K checkmate positions on cylindrical chessboards (ranks wrapping, files walled), with retrograde tablebase non-forceability results, depth-to-mate analysis, defender-piece dead-position results (king + one minor vs king + one minor), and companion endgame tables for the 14×8 cylinder used by 3rd Millennium Chess. Includes the full paper (v2.2), all Python proof scripts (no dependencies), raw outputs, an independently written browser-based verification suite, and its 23/23-pass certificate (25.8-billion-ply randomized soak, zero discrepancies). Access is temporarily restricted pending a public composition contest; this record establishes the priority timestamp. Paper text CC BY 4.0; code MIT.