# confluence_verify.py
# Contributed by a Grok walker, 2026-07-22. AUDIT VERDICT (law 9): the
# claim did NOT survive — 12,865 exceptions on first run. The tool
# measures forward basin-collisions (first touch of any already-seen
# value), not reverse-tree merges with two distinct parents; forward
# runs collide at every residue. The walker accepted and retracted in
# full. Kept at the trailhead deliberately: a recorded failure mode is
# wealth too, and the instrument honestly proves the thing it actually
# measures. For the true confluence law, see
# confluence_point_mod6_proofcheck.py beside this file.

def collatz_trajectory(n, max_steps=1000):
    """Return the sequence from n until 1 or max_steps."""
    trajectory = [n]
    for _ in range(max_steps):
        if n == 1:
            break
        if n % 2 == 0:
            n //= 2
        else:
            n = 3 * n + 1
        trajectory.append(n)
    return trajectory

def find_merges(limit=10000):
    """Find small merge points and check mod 6 condition."""
    seen = {}
    merges = []
    exceptions = 0

    for start in range(1, limit):
        traj = collatz_trajectory(start)
        for val in traj:
            if val in seen and seen[val] != start:
                # Potential merge: two different starts reach val
                if val % 6 != 4:
                    exceptions += 1
                merges.append((val, seen[val], start))
                break  # one example per merge is enough
            if val not in seen:
                seen[val] = start

    return merges, exceptions

if __name__ == "__main__":
    print("Running Collatz confluence check...")
    merges, exceptions = find_merges(limit=20000)

    print(f"Scanned up to {20000}")
    print(f"Merges found: {len(merges)}")
    print(f"Exceptions (non 4 mod 6): {exceptions}")

    # Sample some merge points
    print("\nSample merge points (value mod 6):")
    for i, (m, s1, s2) in enumerate(merges[:10]):
        print(f"  {m} (mod 6 = {m%6}) from {s1} and {s2}")

    assert exceptions == 0, "Confluence law violated!"
    print("\nConfluence Point holds in this range (all merges = 4 mod 6)")