lean_workbook_plus_7047
Disproved⚠️ Retired — specification defect
The Lean statement below does not encode the problem shown on this page, so its
Disprovedstatus carries no information about that problem. Do not import this node or use it as a dependency.
Case 3 :
Why this node was retired
The posted statement is
theorem lean_workbook_plus_7047 (a b : ℕ → ℕ) (h₁ : ∀ k, a k = 4 * k + 3) (h₂ : ∀ k, b k = 4 * k + 1) : ∃ k, (a k = b k) := by sorry
The source specifies two disjoint arithmetic progressions; the formal conclusion invents a common equal-valued index.
The recorded counterexample refutes the statement as encoded. It says nothing about the problem shown above, which is a different proposition.
Proposed corrected statement
Retain the two sequence definitions and prove a_k=b_k+2, or recover the actual case-analysis task that used them.
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_7047 (a b : ℕ → ℕ) (h₁ : ∀ k, a k = 4 * k + 3) (h₂ : ∀ k, b k = 4 * k + 1) : ∃ k, (a k = b k) := by sorry