Proof of `Håstad hardness implies tight inapproximability in triangle-free graphs`
groundedproofs/Lax47Proofs/Main.lean · lax-47
What this proof establishes
no assumptions
thm✓
Lax47.Theorem12Assuming the claims on the left, the claim on the right holds — checked by the archive's pipeline. Proof code is not displayed here.
Description
The polynomial-cutoff randomized blow-up converts a purported triangle-free approximation into a bounded-error, polynomial-step solver for Håstad's general-graph promise gap. Applying the Håstad premise proves the triangle-free conclusion.