The first eleven numbers sum to fifty-five

Exercise · sum_range_eleven

The first eleven numbers sum to fifty-five: $0 + 1 + \dots + 10 = 55$ .

Formal statement · Lean 4.lean

theorem sum_range_eleven : (List.range 11).foldl (· + ·) 0 = 55 := by
  sorry

Proof. sorry

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