Description: Lemma for sseqp1 . (Contributed by Thierry Arnoux, 25-Apr-2019)
| Ref | Expression | ||
|---|---|---|---|
| Hypotheses | iwrdsplit.s | ||
| iwrdsplit.f | |||
| iwrdsplit.n | |||
| Assertion | subiwrd | 
| Step | Hyp | Ref | Expression | 
|---|---|---|---|
| 1 | iwrdsplit.s | ||
| 2 | iwrdsplit.f | ||
| 3 | iwrdsplit.n | ||
| 4 | fzo0ssnn0 | ||
| 5 | fssres | ||
| 6 | 2 4 5 | sylancl | |
| 7 | iswrdi | ||
| 8 | 6 7 | syl |