Replay the Erdős 12 prime-square good-set proof

[DomTheDeveloper]

Green result

The exact historical proof now compiles against the current Erdős 12 definitions and pinned Lean toolchain.

It proves that

{p^2 | p is prime and p ≡ 3 mod 4}

is a good set: the set is infinite, and its elements satisfy the required divisibility obstruction.

Immutable provenance

• Historical source blob: 551b4c3b82a0b446bdbe314ac487754fcc265d0a
• Audit branch head: b43b12d674de0c879c64b82176a64a231f1a73e3
• Focused run: 30214058880

The run passed current catalog-module build, exact theorem extraction, no-hole/no-trust scan, complete compilation, and exact theorem axiom inspection.

Axiom footprint:

[propext, Classical.choice, Quot.sound]

No sorryAx or compiler-trust dependency appears. One historical ZMod lemma emits a deprecation warning and should be modernized during canonical restoration.

Status

Green proof recovery. The current admitted textbook declaration still needs a focused restoration/style-cleanup patch before promotion to _PRs/ready/. This audit-only PR should not merge.

[github-actions]

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