Description: Lemma 1 for pmtrdifel . (Contributed by AV, 15-Jan-2019)
Ref | Expression | ||
---|---|---|---|
Hypotheses | pmtrdifel.t | |
|
pmtrdifel.r | |
||
pmtrdifel.0 | |
||
Assertion | pmtrdifellem1 | |
Step | Hyp | Ref | Expression |
---|---|---|---|
1 | pmtrdifel.t | |
|
2 | pmtrdifel.r | |
|
3 | pmtrdifel.0 | |
|
4 | eqid | |
|
5 | 4 1 | pmtrfb | |
6 | difsnexi | |
|
7 | f1of | |
|
8 | fdm | |
|
9 | difssd | |
|
10 | dmss | |
|
11 | 9 10 | syl | |
12 | difssd | |
|
13 | sseq1 | |
|
14 | 12 13 | mpbird | |
15 | 11 14 | sstrd | |
16 | 7 8 15 | 3syl | |
17 | id | |
|
18 | eqid | |
|
19 | 18 2 | pmtrrn | |
20 | 3 19 | eqeltrid | |
21 | 6 16 17 20 | syl3an | |
22 | 5 21 | sylbi | |