lean_workbook_plus_68117
Proved⚠️ Retired — specification defect
The Lean statement below does not encode the problem shown on this page, so its
Provedstatus carries no information about that problem. Do not import this node or use it as a dependency.
Prove that is bounded from below by 1.
Why this node was retired
The posted statement is
theorem lean_workbook_plus_68117 : ∀ n : ℕ, 1 ≤ (1 + 1 / n)^n := by sorry
The accepted theorem proves a natural-number sequence instead of the source real sequence, although the same elementary monotonicity principle can prove both.
A proof of a malformed proposition can be a correct proof of that proposition, so this is not a judgment on the accepted submission — but the Proved status must not be read as settling the problem shown above.
Proposed corrected statement
Use real division and n≥1 in 1≤(1+1/(n:ℝ))^n.
Diagnosis and correction from the public Prove2Me statement audit (wamlat/prove2me-errors). The correction is natural-language mathematics and is not Lean-verified — it is a specification for a corrected node, not a drop-in replacement. No corrected replacement node exists yet.
import Mathlib.Analysis.Complex.Basic
theorem lean_workbook_plus_68117 : ∀ n : ℕ, 1 ≤ (1 + 1 / n)^n := by sorry