Description: A condition for an atom to be less than or equal to a lattice element. Part of proof of Lemma A in Crawley p. 112. (Contributed by NM, 28-Apr-2012) (New usage is discouraged.)
Ref | Expression | ||
---|---|---|---|
Hypotheses | atomle.b | |
|
atomle.l | |
||
atomle.j | |
||
atomle.a | |
||
Assertion | exatleN | |
Step | Hyp | Ref | Expression |
---|---|---|---|
1 | atomle.b | |
|
2 | atomle.l | |
|
3 | atomle.j | |
|
4 | atomle.a | |
|
5 | simpl32 | |
|
6 | simp11l | |
|
7 | 6 | hllatd | |
8 | simp122 | |
|
9 | 1 4 | atbase | |
10 | 8 9 | syl | |
11 | simp121 | |
|
12 | 1 4 | atbase | |
13 | 11 12 | syl | |
14 | simp123 | |
|
15 | 1 4 | atbase | |
16 | 14 15 | syl | |
17 | 1 3 | latjcl | |
18 | 7 13 16 17 | syl3anc | |
19 | simp11r | |
|
20 | 14 8 11 | 3jca | |
21 | simp2 | |
|
22 | 6 20 21 | 3jca | |
23 | simp133 | |
|
24 | 2 3 4 | hlatexch1 | |
25 | 22 23 24 | sylc | |
26 | simp131 | |
|
27 | simp3 | |
|
28 | 1 2 3 | latjle12 | |
29 | 7 13 16 19 28 | syl13anc | |
30 | 26 27 29 | mpbi2and | |
31 | 1 2 7 10 18 19 25 30 | lattrd | |
32 | 31 | 3expia | |
33 | 5 32 | mtod | |
34 | 33 | ex | |
35 | 34 | necon4ad | |
36 | simp31 | |
|
37 | breq1 | |
|
38 | 36 37 | syl5ibrcom | |
39 | 35 38 | impbid | |