Metamath Proof Explorer


Theorem oalim2cl

Description: The ordinal sum of any ordinal with a limit ordinal on the right is a limit ordinal. (Contributed by RP, 6-Feb-2025)

Ref Expression
Assertion oalim2cl ⊢ A ∈ On ∧ Lim ⁡ B ∧ B ∈ V → Lim ⁡ A + 𝑜 B

Proof

Step Hyp Ref Expression
1 simp1 ⊢ A ∈ On ∧ Lim ⁡ B ∧ B ∈ V → A ∈ On
2 simp3 ⊢ A ∈ On ∧ Lim ⁡ B ∧ B ∈ V → B ∈ V
3 simp2 ⊢ A ∈ On ∧ Lim ⁡ B ∧ B ∈ V → Lim ⁡ B
4 oalimcl ⊢ A ∈ On ∧ B ∈ V ∧ Lim ⁡ B → Lim ⁡ A + 𝑜 B
5 1 2 3 4 syl12anc ⊢ A ∈ On ∧ Lim ⁡ B ∧ B ∈ V → Lim ⁡ A + 𝑜 B