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Mirrors > Home > NFE Home > Th. List > df-0c | Unicode version |
Description: Define cardinal zero. (Contributed by SF, 12-Jan-2015.) |
Ref | Expression |
---|---|
df-0c |
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Step | Hyp | Ref | Expression |
---|---|---|---|
1 | c0c 4374 |
. 2
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2 | c0 3550 |
. . 3
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3 | 2 | csn 3737 |
. 2
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4 | 1, 3 | wceq 1642 |
1
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Colors of variables: wff setvar class |
This definition is referenced by: 0cex 4392 0cnsuc 4401 addcid1 4405 el0c 4421 nnsucelr 4428 nndisjeq 4429 ssfin 4470 0ceven 4505 lec0cg 6198 |
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