Description: A path homotopy is a continuous function. (Contributed by Mario Carneiro, 23-Feb-2015)
| Ref | Expression | ||
|---|---|---|---|
| Hypotheses | isphtpy.2 | ||
| isphtpy.3 | |||
| Assertion | phtpycn |
| Step | Hyp | Ref | Expression |
|---|---|---|---|
| 1 | isphtpy.2 | ||
| 2 | isphtpy.3 | ||
| 3 | 1 2 | phtpyhtpy | |
| 4 | iitopon | ||
| 5 | 4 | a1i | |
| 6 | 5 1 2 | htpycn | |
| 7 | 3 6 | sstrd |