Reverse-engineer the RC2 cipher's secret table

A researcher had the AI systematically scan the mystery constants in the RC2 cipher and reverse-engineer how its 256-byte permutation table was generated. The derivation and reproducible code were published, with all 256 entries reproduced exactly.

How it works

Point the AI at the mystery constants
It systematically scans candidate constructions
Derivation found
All 256 entries reproduced exactly
Publish write-up and code

Why it’s worth knowing

An open cryptography puzzle from the 1990s fell to an agent systematically searching the derivation space.

Where it’s from

Summarized from a public post on news.ycombinator.com. See the original ↗

Upgraded prompt

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