Description: No element covers the lattice unity. (Contributed by NM, 8-Jul-2013)
Ref | Expression | ||
---|---|---|---|
Hypotheses | ncvr1.b | |
|
ncvr1.u | |
||
ncvr1.c | |
||
Assertion | ncvr1 | |
Step | Hyp | Ref | Expression |
---|---|---|---|
1 | ncvr1.b | |
|
2 | ncvr1.u | |
|
3 | ncvr1.c | |
|
4 | eqid | |
|
5 | 1 4 2 | ople1 | |
6 | opposet | |
|
7 | 6 | ad2antrr | |
8 | 1 2 | op1cl | |
9 | 8 | ad2antrr | |
10 | simplr | |
|
11 | simpr | |
|
12 | eqid | |
|
13 | 1 4 12 | pltnle | |
14 | 7 9 10 11 13 | syl31anc | |
15 | 14 | ex | |
16 | 5 15 | mt2d | |
17 | simpll | |
|
18 | 8 | ad2antrr | |
19 | simplr | |
|
20 | simpr | |
|
21 | 1 12 3 | cvrlt | |
22 | 17 18 19 20 21 | syl31anc | |
23 | 16 22 | mtand | |