lean_workbook_plus_3413
OpenDerive from the factorial definition of combinations.
Preamble
import Mathlib.Analysis.Complex.Basic
Formal statement
theorem lean_workbook_plus_3413 : ∀ x : ℕ, choose x 2 = (x^2 - x) / 2 := by sorry
Source
Derive from the factorial definition of combinations.
import Mathlib.Analysis.Complex.Basic
theorem lean_workbook_plus_3413 : ∀ x : ℕ, choose x 2 = (x^2 - x) / 2 := by sorry