Description: _om is closed under multiplication. Inference form of nnmcl . (Contributed by Scott Fenton, 20-Apr-2012)
Ref | Expression | ||
---|---|---|---|
Hypotheses | nncli.1 | ⊢ 𝐴 ∈ ω | |
nncli.2 | ⊢ 𝐵 ∈ ω | ||
Assertion | nnmcli | ⊢ ( 𝐴 ·o 𝐵 ) ∈ ω |
Step | Hyp | Ref | Expression |
---|---|---|---|
1 | nncli.1 | ⊢ 𝐴 ∈ ω | |
2 | nncli.2 | ⊢ 𝐵 ∈ ω | |
3 | nnmcl | ⊢ ( ( 𝐴 ∈ ω ∧ 𝐵 ∈ ω ) → ( 𝐴 ·o 𝐵 ) ∈ ω ) | |
4 | 1 2 3 | mp2an | ⊢ ( 𝐴 ·o 𝐵 ) ∈ ω |