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| author | Andreas Grois <andi@grois.info> | 2024-12-14 00:09:46 +0100 |
|---|---|---|
| committer | Andreas Grois <andi@grois.info> | 2024-12-14 00:09:46 +0100 |
| commit | 8223584095273bc7bdf7b7dc65a6e168350cdf57 (patch) | |
| tree | 2934a22693564082e78d896d98769e0ddc0e9996 /Common/Nat.lean | |
| parent | 4784df61d4858f9f470327e46822aabf2f7eff52 (diff) | |
Begin Day16
Diffstat (limited to 'Common/Nat.lean')
| -rw-r--r-- | Common/Nat.lean | 3 |
1 files changed, 3 insertions, 0 deletions
diff --git a/Common/Nat.lean b/Common/Nat.lean index 9d0ee29..bc66a09 100644 --- a/Common/Nat.lean +++ b/Common/Nat.lean @@ -23,3 +23,6 @@ theorem lt_of_pred_lt {a b : Nat} (h₁ : a < b.pred) : (a < b) := theorem lt_imp_pred_lt {a b : Nat} (h₁ : a < b) : (a.pred < b) := Nat.lt_of_le_of_lt (Nat.pred_le a) h₁ + +theorem le_of_add_le {a b c d : Nat} (h₁ : a ≤ b + c) (h₂ : c ≤ d) : a ≤ b + d := + Nat.le_trans h₁ (Nat.add_le_add_left h₂ b) |