Lean-Workbook Syntax 81229: The admissible auditorium seat counts sum to 615
ProvedWorkbookSyntax.plus_81229lean-workbookrepaired-notationsource-checked
The sum of all divisors of 2050 lying between 150 and 431 inclusive is 615.
Source: Lean-Workbook row lean_workbook_plus_81229 (Apache-2.0), original record. This corrected declaration replaces the obsolete finite sum/product binder in with ∈ and restores required imports or namespaces. Ranges, casts, quantifiers, and mathematical expressions are preserved.
Preamble
import Mathlib.Algebra.BigOperators.Intervals
Formal statement
theorem WorkbookSyntax.plus_81229 (n : ℕ) (h₁ : 150 ≤ n) (h₂ : n ≤ 431) (h₃ : n ∣ 2050) : ∑ k ∈ Finset.filter (λ x => x ∣ 2050) (Finset.Icc 150 431), k = 615 := by sorry
Source