Metamath Proof Explorer
Description: Deduction of abstraction subclass from implication. (Contributed by NM, 20-Jan-2006) (Proof shortened by SN, 22-Dec-2024)
|
|
Ref |
Expression |
|
Hypothesis |
abssdv.1 |
|
|
Assertion |
abssdv |
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Proof
Step |
Hyp |
Ref |
Expression |
1 |
|
abssdv.1 |
|
2 |
1
|
ss2abdv |
|
3 |
|
abid1 |
|
4 |
2 3
|
sseqtrrdi |
|