Description: Ordinal 1 is strictly dominated by ordinal 2. (Contributed by NM, 4-Apr-2007)
Ref | Expression | ||
---|---|---|---|
Assertion | 1sdom2 | ⊢ 1o ≺ 2o |
Step | Hyp | Ref | Expression |
---|---|---|---|
1 | 1onn | ⊢ 1o ∈ ω | |
2 | php4 | ⊢ ( 1o ∈ ω → 1o ≺ suc 1o ) | |
3 | 1 2 | ax-mp | ⊢ 1o ≺ suc 1o |
4 | df-2o | ⊢ 2o = suc 1o | |
5 | 3 4 | breqtrri | ⊢ 1o ≺ 2o |