Description: First direction for ustbas . (Contributed by Thierry Arnoux, 16-Nov-2017)
Ref | Expression | ||
---|---|---|---|
Assertion | elrnust | |
Step | Hyp | Ref | Expression |
---|---|---|---|
1 | elfvdm | |
|
2 | fveq2 | |
|
3 | 2 | eleq2d | |
4 | 3 | rspcev | |
5 | 1 4 | mpancom | |
6 | ustfn | |
|
7 | fnfun | |
|
8 | elunirn | |
|
9 | 6 7 8 | mp2b | |
10 | 5 9 | sylibr | |