Description: The topology component of the extended real number structure. (Contributed by Mario Carneiro, 21-Aug-2015)
Ref | Expression | ||
---|---|---|---|
Assertion | xrstopn |
Step | Hyp | Ref | Expression |
---|---|---|---|
1 | letopon | ||
2 | xrsbas | ||
3 | xrstset | ||
4 | 2 3 | topontopn | |
5 | 1 4 | ax-mp |