Description: Property of an element above a covering. (Contributed by NM, 7-Dec-2012) (New usage is discouraged.)
Ref | Expression | ||
---|---|---|---|
Hypotheses | cvrletr.b | |
|
cvrletr.l | |
||
cvrletr.s | |
||
cvrletr.c | |
||
Assertion | cvrletrN | |
Step | Hyp | Ref | Expression |
---|---|---|---|
1 | cvrletr.b | |
|
2 | cvrletr.l | |
|
3 | cvrletr.s | |
|
4 | cvrletr.c | |
|
5 | simpll | |
|
6 | simplr1 | |
|
7 | simplr2 | |
|
8 | simpr | |
|
9 | 1 3 4 | cvrlt | |
10 | 5 6 7 8 9 | syl31anc | |
11 | 1 2 3 | pltletr | |
12 | 11 | adantr | |
13 | 10 12 | mpand | |
14 | 13 | expimpd | |