Work

A machine-checked proof of the Dong-Yang classification of optimal (n,4) binary codes for BSCs

Year: 2026
Type: preprint
Abstract: We present a machine-checked Lean~4 formalization of Dong and Yang's classification of optimal finite-length $(n,4)$ binary block codes for binary symmetric channels. The formalization was developed mainly by feeding the paper's proofs to an AI tool. To establish correctness, the authors verified the main theorem statements in Lean and the accepted axioms. This note discusses the corrections and simplifications made to the AI-generated formalization, and records discrepancies found in the paper during the formalization. The Lean code is available at https://github.com/shhyang/n4code_lean.
Language: English
Open Access status: green
OpenAlex ID: W7212311049
Cites: 10
Cited by: 1
Related to: 10