Description: A theorem is interchangeable. (Contributed by SN, 4-May-2024)
Ref | Expression | ||
---|---|---|---|
Hypothesis | icht.1 | ||
Assertion | icht |
Step | Hyp | Ref | Expression |
---|---|---|---|
1 | icht.1 | ||
2 | 1 | sbt | |
3 | 2 | sbt | |
4 | 3 | sbt | |
5 | 4 1 | 2th | |
6 | 5 | gen2 | |
7 | df-ich | ||
8 | 6 7 | mpbir |