AMSCO + disrupted columnar transposition (Swapped, Nihilist)

AMSCO + disrupted columnar transposition (Swapped, Nihilist) at widths 5-14

In plain English: AMSCO + disrupted columnar transposition (Swapped, Nihilist) at widths 5-14 — using a columnar transposition variant that alternates between 1 and 2 characters per cell. Every possible combination was tested (800 thousand configurations) — none produced a valid solution. Best match: 15/24 known letters — slightly above random, almost certainly coincidence. This approach is ruled out within the tested scope.

NOISE: 15/24 at period 8 only; period 7 = 0/24; Bean FAIL Tier 2

How to read this record

Verdict – NOISE (no better than random guessing), INTERESTING (slightly above random, almost certainly coincidence), SIGNAL (statistically unusual, warrants investigation), or FULL MATCH (all 24 known letters correct).
Confidence Tier – Tier 1 = mathematical proof (permanent). Tier 2 = every possibility tested. Tier 3 = partially tested. Tier 4 = not yet tested.
Configs Tested – How many different key/parameter combinations were tried.
Best Score – How many of the 24 known plaintext letters the best attempt matched (out of 24).
Keystream Consistency (Bean) – Whether the key values at different positions are mathematically consistent with each other.
Scope Limitations – What this elimination does not rule out.

Configs Tested: 800,000
Best Score: 15 / 24 known letters matched · above random, likely coincidence (random guess would score: 0.0)
Keystream Consistency (Bean): FAIL
Checks whether the key values at different positions are mathematically consistent with each other.
Confidence: Tier 2: Exhaustive search under stated assumptions. Does not eliminate multi-layer variants.
Date Tested: 2026-02-15
Script: scripts/transposition/other/e_s_22_amsco_disrupted.py

Scope Limitations

This elimination does not rule out:

Single-layer only. Tests AMSCO (1-2 alternating), Nihilist transposition, and swapped columnar at widths 5-14.

Assumptions

Direct positional correspondence
Periodic substitution (Vigenere/Beaufort) at periods tested
Standard AMSCO alternating fill pattern

Reproduce

PYTHONPATH=src python3 -u scripts/transposition/other/e_s_22_amsco_disrupted.py

Requires the kryptos repo, Python 3.11+, PYTHONPATH=src.

Found an error? Report on GitHub