Description: The Teichmüller-Tukey Lemma ttukey with a slightly stronger conclusion: we can set up the maximal element of A so that it also contains some given B e. A as a subset. (Contributed by Mario Carneiro, 15-May-2015)
Ref | Expression | ||
---|---|---|---|
Assertion | ttukey2g | |
Step | Hyp | Ref | Expression |
---|---|---|---|
1 | difss | |
|
2 | ssnum | |
|
3 | 1 2 | mpan2 | |
4 | isnum3 | |
|
5 | bren | |
|
6 | 4 5 | bitri | |
7 | simp1 | |
|
8 | simp2 | |
|
9 | simp3 | |
|
10 | dmeq | |
|
11 | 10 | unieqd | |
12 | 10 11 | eqeq12d | |
13 | 10 | eqeq1d | |
14 | rneq | |
|
15 | 14 | unieqd | |
16 | 13 15 | ifbieq2d | |
17 | id | |
|
18 | 17 11 | fveq12d | |
19 | 11 | fveq2d | |
20 | 19 | sneqd | |
21 | 18 20 | uneq12d | |
22 | 21 | eleq1d | |
23 | 22 20 | ifbieq1d | |
24 | 18 23 | uneq12d | |
25 | 12 16 24 | ifbieq12d | |
26 | 25 | cbvmptv | |
27 | recseq | |
|
28 | 26 27 | ax-mp | |
29 | 7 8 9 28 | ttukeylem7 | |
30 | 29 | 3expib | |
31 | 30 | exlimiv | |
32 | 6 31 | sylbi | |
33 | 3 32 | syl | |
34 | 33 | 3impib | |