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| Mirrors > Home > NFE Home > Th. List > 2mo | Unicode version | ||
| Description: Two equivalent expressions for double "at most one." (Contributed by NM, 2-Feb-2005.) (Revised by Mario Carneiro, 17-Oct-2016.) | 
| Ref | Expression | 
|---|---|
| 2mo | 
 | 
| Step | Hyp | Ref | Expression | 
|---|---|---|---|
| 1 | equequ2 1686 | 
. . . . . . 7
 | |
| 2 | equequ2 1686 | 
. . . . . . 7
 | |
| 3 | 1, 2 | bi2anan9 843 | 
. . . . . 6
 | 
| 4 | 3 | imbi2d 307 | 
. . . . 5
 | 
| 5 | 4 | 2albidv 1627 | 
. . . 4
 | 
| 6 | 5 | cbvex2v 2007 | 
. . 3
 | 
| 7 | nfv 1619 | 
. . . . . . . . 9
 | |
| 8 | nfv 1619 | 
. . . . . . . . 9
 | |
| 9 | nfs1v 2106 | 
. . . . . . . . . 10
 | |
| 10 | nfv 1619 | 
. . . . . . . . . 10
 | |
| 11 | 9, 10 | nfim 1813 | 
. . . . . . . . 9
 | 
| 12 | nfs1v 2106 | 
. . . . . . . . . . 11
 | |
| 13 | 12 | nfsb 2109 | 
. . . . . . . . . 10
 | 
| 14 | nfv 1619 | 
. . . . . . . . . 10
 | |
| 15 | 13, 14 | nfim 1813 | 
. . . . . . . . 9
 | 
| 16 | sbequ12 1919 | 
. . . . . . . . . . 11
 | |
| 17 | sbequ12 1919 | 
. . . . . . . . . . 11
 | |
| 18 | 16, 17 | sylan9bbr 681 | 
. . . . . . . . . 10
 | 
| 19 | equequ1 1684 | 
. . . . . . . . . . 11
 | |
| 20 | equequ1 1684 | 
. . . . . . . . . . 11
 | |
| 21 | 19, 20 | bi2anan9 843 | 
. . . . . . . . . 10
 | 
| 22 | 18, 21 | imbi12d 311 | 
. . . . . . . . 9
 | 
| 23 | 7, 8, 11, 15, 22 | cbval2 2004 | 
. . . . . . . 8
 | 
| 24 | 23 | biimpi 186 | 
. . . . . . 7
 | 
| 25 | 24 | ancli 534 | 
. . . . . 6
 | 
| 26 | alcom 1737 | 
. . . . . . . . 9
 | |
| 27 | 8, 15 | aaan 1884 | 
. . . . . . . . . 10
 | 
| 28 | 27 | albii 1566 | 
. . . . . . . . 9
 | 
| 29 | 26, 28 | bitri 240 | 
. . . . . . . 8
 | 
| 30 | 29 | albii 1566 | 
. . . . . . 7
 | 
| 31 | nfv 1619 | 
. . . . . . . 8
 | |
| 32 | 11 | nfal 1842 | 
. . . . . . . 8
 | 
| 33 | 31, 32 | aaan 1884 | 
. . . . . . 7
 | 
| 34 | 30, 33 | bitri 240 | 
. . . . . 6
 | 
| 35 | 25, 34 | sylibr 203 | 
. . . . 5
 | 
| 36 | prth 554 | 
. . . . . . . 8
 | |
| 37 | equtr2 1688 | 
. . . . . . . . . 10
 | |
| 38 | equtr2 1688 | 
. . . . . . . . . 10
 | |
| 39 | 37, 38 | anim12i 549 | 
. . . . . . . . 9
 | 
| 40 | 39 | an4s 799 | 
. . . . . . . 8
 | 
| 41 | 36, 40 | syl6 29 | 
. . . . . . 7
 | 
| 42 | 41 | 2alimi 1560 | 
. . . . . 6
 | 
| 43 | 42 | 2alimi 1560 | 
. . . . 5
 | 
| 44 | 35, 43 | syl 15 | 
. . . 4
 | 
| 45 | 44 | exlimivv 1635 | 
. . 3
 | 
| 46 | 6, 45 | sylbir 204 | 
. 2
 | 
| 47 | alrot4 1739 | 
. . . . 5
 | |
| 48 | pm3.21 435 | 
. . . . . . . . . . . 12
 | |
| 49 | 48 | imim1d 69 | 
. . . . . . . . . . 11
 | 
| 50 | 13, 49 | alimd 1764 | 
. . . . . . . . . 10
 | 
| 51 | 9, 50 | alimd 1764 | 
. . . . . . . . 9
 | 
| 52 | 51 | com12 27 | 
. . . . . . . 8
 | 
| 53 | 52 | alimi 1559 | 
. . . . . . 7
 | 
| 54 | exim 1575 | 
. . . . . . 7
 | |
| 55 | 53, 54 | syl 15 | 
. . . . . 6
 | 
| 56 | 55 | alimi 1559 | 
. . . . 5
 | 
| 57 | 47, 56 | sylbi 187 | 
. . . 4
 | 
| 58 | exim 1575 | 
. . . 4
 | |
| 59 | 57, 58 | syl 15 | 
. . 3
 | 
| 60 | alnex 1543 | 
. . . . . 6
 | |
| 61 | 60 | albii 1566 | 
. . . . 5
 | 
| 62 | alnex 1543 | 
. . . . 5
 | |
| 63 | 61, 62 | bitri 240 | 
. . . 4
 | 
| 64 | nfv 1619 | 
. . . . . . 7
 | |
| 65 | nfv 1619 | 
. . . . . . 7
 | |
| 66 | 9 | nfn 1793 | 
. . . . . . 7
 | 
| 67 | 13 | nfn 1793 | 
. . . . . . 7
 | 
| 68 | 18 | notbid 285 | 
. . . . . . 7
 | 
| 69 | 64, 65, 66, 67, 68 | cbval2 2004 | 
. . . . . 6
 | 
| 70 | pm2.21 100 | 
. . . . . . 7
 | |
| 71 | 70 | 2alimi 1560 | 
. . . . . 6
 | 
| 72 | 69, 71 | sylbir 204 | 
. . . . 5
 | 
| 73 | 19.8a 1756 | 
. . . . . 6
 | |
| 74 | 73 | 19.23bi 1759 | 
. . . . 5
 | 
| 75 | 72, 74 | syl 15 | 
. . . 4
 | 
| 76 | 63, 75 | sylbir 204 | 
. . 3
 | 
| 77 | 59, 76 | pm2.61d1 151 | 
. 2
 | 
| 78 | 46, 77 | impbii 180 | 
1
 | 
| Colors of variables: wff setvar class | 
| Syntax hints:    | 
| This theorem was proved from axioms: ax-mp 5 ax-1 6 ax-2 7 ax-3 8 ax-gen 1546 ax-5 1557 ax-17 1616 ax-9 1654 ax-8 1675 ax-6 1729 ax-7 1734 ax-11 1746 ax-12 1925 | 
| This theorem depends on definitions: df-bi 177 df-an 360 df-tru 1319 df-ex 1542 df-nf 1545 df-sb 1649 | 
| This theorem is referenced by: 2mos 2283 2eu6 2289 | 
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