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Related theorems Unicode version |
| Description: Every power class contains the empty set. |
| Ref | Expression |
|---|---|
| 0elpw |
|
| Step | Hyp | Ref | Expression |
|---|---|---|---|
| 1 | 0ss 2353 |
. 2
| |
| 2 | 0ex 2766 |
. . 3
| |
| 3 | 2 | elpw 2456 |
. 2
|
| 4 | 1, 3 | mpbir 197 |
1
|
| Colors of variables: wff set class |
| Syntax hints: |
| This theorem is referenced by: bcth 8117 |
| This theorem was proved from axioms: ax-1 4 ax-2 5 ax-3 6 ax-mp 7 ax-7 1003 ax-gen 1004 ax-8 1005 ax-10 1007 ax-11 1008 ax-12 1009 ax-14 1011 ax-17 1012 ax-4 1014 ax-5o 1016 ax-6o 1019 ax-9o 1164 ax-10o 1182 ax-16 1252 ax-11o 1260 ax-ext 1504 ax-nul 2765 |
| This theorem depends on definitions: df-bi 154 df-or 231 df-an 232 df-ex 1022 df-sb 1214 df-eu 1424 df-mo 1425 df-clab 1510 df-cleq 1515 df-clel 1518 df-ne 1634 df-v 1859 df-dif 2100 df-in 2102 df-ss 2104 df-nul 2332 df-pw 2454 |