Description: Properties of a walk between two vertices. (Contributed by Alexander van der Vekens, 12-Dec-2017) (Revised by AV, 31-Dec-2020) (Proof shortened by AV, 16-Jan-2021)
Ref | Expression | ||
---|---|---|---|
Hypothesis | wlkson.v | |
|
Assertion | wlkonprop | |
Step | Hyp | Ref | Expression |
---|---|---|---|
1 | wlkson.v | |
|
2 | 1 | fvexi | |
3 | df-wlkson | |
|
4 | 1 | wlkson | |
5 | 4 | 3adant1 | |
6 | fveq2 | |
|
7 | 6 1 | eqtr4di | |
8 | fveq2 | |
|
9 | 8 | breqd | |
10 | 9 | 3anbi1d | |
11 | 3 5 7 7 10 | bropfvvvv | |
12 | 2 2 11 | mp2an | |
13 | 3anass | |
|
14 | 13 | anbi1i | |
15 | df-3an | |
|
16 | 14 15 | bitr4i | |
17 | 12 16 | sylibr | |
18 | 1 | iswlkon | |
19 | 18 | 3adantl1 | |
20 | 19 | biimpd | |
21 | 20 | imdistani | |
22 | 17 21 | mpancom | |
23 | df-3an | |
|
24 | 22 23 | sylibr | |