Description: Bound-variable hypothesis builder for well-founded successor. (Contributed by Scott Fenton, 13-Jun-2018) (Proof shortened by AV, 10-Oct-2021)
Ref | Expression | ||
---|---|---|---|
Hypotheses | nfwsuc.1 | |
|
nfwsuc.2 | |
||
nfwsuc.3 | |
||
Assertion | nfwsuc | |
Step | Hyp | Ref | Expression |
---|---|---|---|
1 | nfwsuc.1 | |
|
2 | nfwsuc.2 | |
|
3 | nfwsuc.3 | |
|
4 | df-wsuc | |
|
5 | 1 | nfcnv | |
6 | 5 2 3 | nfpred | |
7 | 6 2 1 | nfinf | |
8 | 4 7 | nfcxfr | |