Public Mathlib landmark · existing upstream theorem · read-only

Technical Lean evidence record

Checked Artifact: Basel Problem (mathlib)

Proof Atlas collected build, no-sorry, axiom, and clean-source evidence directly from the pinned upstream declaration.

ProofAtlas record

What has been checked

Upstream indexedPinned source bytes verified locally
Locally reproducedExact upstream declaration replayed
Reviewed pageCurrent public presentation reviewed
Accepted Atlas resultNot recorded for the preferred artifact

These states distinguish upstream identity, local reproduction, review, and Atlas acceptance. This page is part of the public, read-only Mathlib landmark collection.

Mechanical evidence

Declaration checked
hasSum_zeta_two
Module
Mathlib.NumberTheory.ZetaValues
Source file checked
Mathlib/NumberTheory/ZetaValues.lean
Package commit
5e932f97dd25535344f80f9dd8da3aab83df0fe6
Build
passed · transcript retained
Unfinished proof steps
None found by the recorded no-sorry scan
Axiom closure
Classical.choice, Quot.sound, propext
Clean collection provenance
Recorded

Evidence boundary

This page presents Mathlib's real HasSum statement for n ↦ 1/(n:ℝ)^2 with value π^2/6. Its natural-number indexing includes n = 0, whose term is zero under Lean's totalized real division, so it represents the usual series over positive integers. The selected declaration is only the exponent-two specialization, not a generic theorem about all zeta values.

This checker record is evidence for the exact formal statement only. It does not establish novelty, transfer a historical acceptance decision, or authorize publication.