Sum of integers below 244

Proved

FiniteTriangular.sum_range_244

by carlok · Sep 25, 2026 · Mathlib 0df444a (Lean v4.33.1)

arithmeticfinite-sum

The sum of the nonnegative integers strictly less than $244$ equals $29646$ . Equivalently, $\\sum_{k=0}^{244-1} k = 244(244-1)/2$ .

Preamble

import Mathlib
open Finset

Formal statement

namespace FiniteTriangular

theorem sum_range_244 : ∑ k ∈ range 244, k = 29646 := by sorry

end FiniteTriangular

Source

Elementary arithmetic series: the sum of the first m positive integers is m(m+1)/2, rewritten on Finset.range.