Metamath Proof Explorer
Description: Core proof of Proposition 55 of Frege1879 p. 50. (Contributed by RP, 24-Dec-2019) (Proof modification is discouraged.)
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Ref |
Expression |
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Assertion |
frege55lem2a |
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Proof
Step |
Hyp |
Ref |
Expression |
1 |
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bicom1 |
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2 |
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frege54cor0a |
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3 |
1 2
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sylib |
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