Description: A word is a zero-based sequence with a recoverable upper limit, deduction version. (Contributed by Thierry Arnoux, 22-Dec-2021)
Ref | Expression | ||
---|---|---|---|
Hypotheses | wrdfd.n | ||
wrdfd.w | |||
Assertion | wrdfd |
Step | Hyp | Ref | Expression |
---|---|---|---|
1 | wrdfd.n | ||
2 | wrdfd.w | ||
3 | wrdf | ||
4 | 2 3 | syl | |
5 | 1 | oveq2d | |
6 | 5 | feq2d | |
7 | 4 6 | mpbird |