| Step | Hyp | Ref | Expression | 
						
							| 1 |  | negsproplem.1 |  | 
						
							| 2 |  | negsproplem2.1 |  | 
						
							| 3 |  | negsfn |  | 
						
							| 4 |  | fnfun |  | 
						
							| 5 | 3 4 | ax-mp |  | 
						
							| 6 |  | fvex |  | 
						
							| 7 | 6 | funimaex |  | 
						
							| 8 | 5 7 | mp1i |  | 
						
							| 9 |  | fvex |  | 
						
							| 10 | 9 | funimaex |  | 
						
							| 11 | 5 10 | mp1i |  | 
						
							| 12 |  | rightssold |  | 
						
							| 13 |  | imass2 |  | 
						
							| 14 | 12 13 | ax-mp |  | 
						
							| 15 | 1 | adantr |  | 
						
							| 16 |  | oldssno |  | 
						
							| 17 | 16 | sseli |  | 
						
							| 18 | 17 | adantl |  | 
						
							| 19 |  | 0sno |  | 
						
							| 20 | 19 | a1i |  | 
						
							| 21 |  | bday0s |  | 
						
							| 22 | 21 | uneq2i |  | 
						
							| 23 |  | un0 |  | 
						
							| 24 | 22 23 | eqtri |  | 
						
							| 25 |  | oldbdayim |  | 
						
							| 26 | 25 | adantl |  | 
						
							| 27 |  | elun1 |  | 
						
							| 28 | 26 27 | syl |  | 
						
							| 29 | 24 28 | eqeltrid |  | 
						
							| 30 | 15 18 20 29 | negsproplem1 |  | 
						
							| 31 | 30 | simpld |  | 
						
							| 32 | 31 | ralrimiva |  | 
						
							| 33 | 3 | fndmi |  | 
						
							| 34 | 16 33 | sseqtrri |  | 
						
							| 35 |  | funimass4 |  | 
						
							| 36 | 5 34 35 | mp2an |  | 
						
							| 37 | 32 36 | sylibr |  | 
						
							| 38 | 14 37 | sstrid |  | 
						
							| 39 |  | leftssold |  | 
						
							| 40 |  | imass2 |  | 
						
							| 41 | 39 40 | ax-mp |  | 
						
							| 42 | 41 37 | sstrid |  | 
						
							| 43 |  | rightssno |  | 
						
							| 44 |  | fvelimab | Could not format  ( ( -us Fn No /\ ( _Right ` A ) C_ No ) -> ( a e. ( -us " ( _Right ` A ) ) <-> E. xR e. ( _Right ` A ) ( -us ` xR ) = a ) ) : No typesetting found for |- ( ( -us Fn No /\ ( _Right ` A ) C_ No ) -> ( a e. ( -us " ( _Right ` A ) ) <-> E. xR e. ( _Right ` A ) ( -us ` xR ) = a ) ) with typecode |- | 
						
							| 45 | 3 43 44 | mp2an | Could not format  ( a e. ( -us " ( _Right ` A ) ) <-> E. xR e. ( _Right ` A ) ( -us ` xR ) = a ) : No typesetting found for |- ( a e. ( -us " ( _Right ` A ) ) <-> E. xR e. ( _Right ` A ) ( -us ` xR ) = a ) with typecode |- | 
						
							| 46 |  | leftssno |  | 
						
							| 47 |  | fvelimab | Could not format  ( ( -us Fn No /\ ( _Left ` A ) C_ No ) -> ( b e. ( -us " ( _Left ` A ) ) <-> E. xL e. ( _Left ` A ) ( -us ` xL ) = b ) ) : No typesetting found for |- ( ( -us Fn No /\ ( _Left ` A ) C_ No ) -> ( b e. ( -us " ( _Left ` A ) ) <-> E. xL e. ( _Left ` A ) ( -us ` xL ) = b ) ) with typecode |- | 
						
							| 48 | 3 46 47 | mp2an | Could not format  ( b e. ( -us " ( _Left ` A ) ) <-> E. xL e. ( _Left ` A ) ( -us ` xL ) = b ) : No typesetting found for |- ( b e. ( -us " ( _Left ` A ) ) <-> E. xL e. ( _Left ` A ) ( -us ` xL ) = b ) with typecode |- | 
						
							| 49 | 45 48 | anbi12i | Could not format  ( ( a e. ( -us " ( _Right ` A ) ) /\ b e. ( -us " ( _Left ` A ) ) ) <-> ( E. xR e. ( _Right ` A ) ( -us ` xR ) = a /\ E. xL e. ( _Left ` A ) ( -us ` xL ) = b ) ) : No typesetting found for |- ( ( a e. ( -us " ( _Right ` A ) ) /\ b e. ( -us " ( _Left ` A ) ) ) <-> ( E. xR e. ( _Right ` A ) ( -us ` xR ) = a /\ E. xL e. ( _Left ` A ) ( -us ` xL ) = b ) ) with typecode |- | 
						
							| 50 |  | reeanv | Could not format  ( E. xR e. ( _Right ` A ) E. xL e. ( _Left ` A ) ( ( -us ` xR ) = a /\ ( -us ` xL ) = b ) <-> ( E. xR e. ( _Right ` A ) ( -us ` xR ) = a /\ E. xL e. ( _Left ` A ) ( -us ` xL ) = b ) ) : No typesetting found for |- ( E. xR e. ( _Right ` A ) E. xL e. ( _Left ` A ) ( ( -us ` xR ) = a /\ ( -us ` xL ) = b ) <-> ( E. xR e. ( _Right ` A ) ( -us ` xR ) = a /\ E. xL e. ( _Left ` A ) ( -us ` xL ) = b ) ) with typecode |- | 
						
							| 51 | 49 50 | bitr4i | Could not format  ( ( a e. ( -us " ( _Right ` A ) ) /\ b e. ( -us " ( _Left ` A ) ) ) <-> E. xR e. ( _Right ` A ) E. xL e. ( _Left ` A ) ( ( -us ` xR ) = a /\ ( -us ` xL ) = b ) ) : No typesetting found for |- ( ( a e. ( -us " ( _Right ` A ) ) /\ b e. ( -us " ( _Left ` A ) ) ) <-> E. xR e. ( _Right ` A ) E. xL e. ( _Left ` A ) ( ( -us ` xR ) = a /\ ( -us ` xL ) = b ) ) with typecode |- | 
						
							| 52 |  | lltropt |  | 
						
							| 53 | 52 | a1i | Could not format  ( ( ph /\ ( xR e. ( _Right ` A ) /\ xL e. ( _Left ` A ) ) ) -> ( _Left ` A ) <  ( _Left ` A ) <
						 | 
						
							| 54 |  | simprr | Could not format  ( ( ph /\ ( xR e. ( _Right ` A ) /\ xL e. ( _Left ` A ) ) ) -> xL e. ( _Left ` A ) ) : No typesetting found for |- ( ( ph /\ ( xR e. ( _Right ` A ) /\ xL e. ( _Left ` A ) ) ) -> xL e. ( _Left ` A ) ) with typecode |- | 
						
							| 55 |  | simprl | Could not format  ( ( ph /\ ( xR e. ( _Right ` A ) /\ xL e. ( _Left ` A ) ) ) -> xR e. ( _Right ` A ) ) : No typesetting found for |- ( ( ph /\ ( xR e. ( _Right ` A ) /\ xL e. ( _Left ` A ) ) ) -> xR e. ( _Right ` A ) ) with typecode |- | 
						
							| 56 | 53 54 55 | ssltsepcd | Could not format  ( ( ph /\ ( xR e. ( _Right ` A ) /\ xL e. ( _Left ` A ) ) ) -> xL  xL 
						 | 
						
							| 57 | 1 | adantr | Could not format  ( ( ph /\ ( xR e. ( _Right ` A ) /\ xL e. ( _Left ` A ) ) ) -> A. x e. No A. y e. No ( ( ( bday ` x ) u. ( bday ` y ) ) e. ( ( bday ` A ) u. ( bday ` B ) ) -> ( ( -us ` x ) e. No /\ ( x  ( -us ` y )  A. x e. No A. y e. No ( ( ( bday ` x ) u. ( bday ` y ) ) e. ( ( bday ` A ) u. ( bday ` B ) ) -> ( ( -us ` x ) e. No /\ ( x  ( -us ` y ) 
						 | 
						
							| 58 | 46 | sseli | Could not format  ( xL e. ( _Left ` A ) -> xL e. No ) : No typesetting found for |- ( xL e. ( _Left ` A ) -> xL e. No ) with typecode |- | 
						
							| 59 | 58 | ad2antll | Could not format  ( ( ph /\ ( xR e. ( _Right ` A ) /\ xL e. ( _Left ` A ) ) ) -> xL e. No ) : No typesetting found for |- ( ( ph /\ ( xR e. ( _Right ` A ) /\ xL e. ( _Left ` A ) ) ) -> xL e. No ) with typecode |- | 
						
							| 60 | 43 | sseli | Could not format  ( xR e. ( _Right ` A ) -> xR e. No ) : No typesetting found for |- ( xR e. ( _Right ` A ) -> xR e. No ) with typecode |- | 
						
							| 61 | 60 | adantr | Could not format  ( ( xR e. ( _Right ` A ) /\ xL e. ( _Left ` A ) ) -> xR e. No ) : No typesetting found for |- ( ( xR e. ( _Right ` A ) /\ xL e. ( _Left ` A ) ) -> xR e. No ) with typecode |- | 
						
							| 62 | 61 | adantl | Could not format  ( ( ph /\ ( xR e. ( _Right ` A ) /\ xL e. ( _Left ` A ) ) ) -> xR e. No ) : No typesetting found for |- ( ( ph /\ ( xR e. ( _Right ` A ) /\ xL e. ( _Left ` A ) ) ) -> xR e. No ) with typecode |- | 
						
							| 63 | 39 | sseli | Could not format  ( xL e. ( _Left ` A ) -> xL e. ( _Old ` ( bday ` A ) ) ) : No typesetting found for |- ( xL e. ( _Left ` A ) -> xL e. ( _Old ` ( bday ` A ) ) ) with typecode |- | 
						
							| 64 | 63 | ad2antll | Could not format  ( ( ph /\ ( xR e. ( _Right ` A ) /\ xL e. ( _Left ` A ) ) ) -> xL e. ( _Old ` ( bday ` A ) ) ) : No typesetting found for |- ( ( ph /\ ( xR e. ( _Right ` A ) /\ xL e. ( _Left ` A ) ) ) -> xL e. ( _Old ` ( bday ` A ) ) ) with typecode |- | 
						
							| 65 |  | oldbdayim | Could not format  ( xL e. ( _Old ` ( bday ` A ) ) -> ( bday ` xL ) e. ( bday ` A ) ) : No typesetting found for |- ( xL e. ( _Old ` ( bday ` A ) ) -> ( bday ` xL ) e. ( bday ` A ) ) with typecode |- | 
						
							| 66 | 64 65 | syl | Could not format  ( ( ph /\ ( xR e. ( _Right ` A ) /\ xL e. ( _Left ` A ) ) ) -> ( bday ` xL ) e. ( bday ` A ) ) : No typesetting found for |- ( ( ph /\ ( xR e. ( _Right ` A ) /\ xL e. ( _Left ` A ) ) ) -> ( bday ` xL ) e. ( bday ` A ) ) with typecode |- | 
						
							| 67 | 12 | a1i |  | 
						
							| 68 | 67 | sselda | Could not format  ( ( ph /\ xR e. ( _Right ` A ) ) -> xR e. ( _Old ` ( bday ` A ) ) ) : No typesetting found for |- ( ( ph /\ xR e. ( _Right ` A ) ) -> xR e. ( _Old ` ( bday ` A ) ) ) with typecode |- | 
						
							| 69 | 68 | adantrr | Could not format  ( ( ph /\ ( xR e. ( _Right ` A ) /\ xL e. ( _Left ` A ) ) ) -> xR e. ( _Old ` ( bday ` A ) ) ) : No typesetting found for |- ( ( ph /\ ( xR e. ( _Right ` A ) /\ xL e. ( _Left ` A ) ) ) -> xR e. ( _Old ` ( bday ` A ) ) ) with typecode |- | 
						
							| 70 |  | oldbdayim | Could not format  ( xR e. ( _Old ` ( bday ` A ) ) -> ( bday ` xR ) e. ( bday ` A ) ) : No typesetting found for |- ( xR e. ( _Old ` ( bday ` A ) ) -> ( bday ` xR ) e. ( bday ` A ) ) with typecode |- | 
						
							| 71 | 69 70 | syl | Could not format  ( ( ph /\ ( xR e. ( _Right ` A ) /\ xL e. ( _Left ` A ) ) ) -> ( bday ` xR ) e. ( bday ` A ) ) : No typesetting found for |- ( ( ph /\ ( xR e. ( _Right ` A ) /\ xL e. ( _Left ` A ) ) ) -> ( bday ` xR ) e. ( bday ` A ) ) with typecode |- | 
						
							| 72 |  | bdayelon | Could not format  ( bday ` xL ) e. On : No typesetting found for |- ( bday ` xL ) e. On with typecode |- | 
						
							| 73 |  | bdayelon | Could not format  ( bday ` xR ) e. On : No typesetting found for |- ( bday ` xR ) e. On with typecode |- | 
						
							| 74 |  | bdayelon |  | 
						
							| 75 |  | onunel | Could not format  ( ( ( bday ` xL ) e. On /\ ( bday ` xR ) e. On /\ ( bday ` A ) e. On ) -> ( ( ( bday ` xL ) u. ( bday ` xR ) ) e. ( bday ` A ) <-> ( ( bday ` xL ) e. ( bday ` A ) /\ ( bday ` xR ) e. ( bday ` A ) ) ) ) : No typesetting found for |- ( ( ( bday ` xL ) e. On /\ ( bday ` xR ) e. On /\ ( bday ` A ) e. On ) -> ( ( ( bday ` xL ) u. ( bday ` xR ) ) e. ( bday ` A ) <-> ( ( bday ` xL ) e. ( bday ` A ) /\ ( bday ` xR ) e. ( bday ` A ) ) ) ) with typecode |- | 
						
							| 76 | 72 73 74 75 | mp3an | Could not format  ( ( ( bday ` xL ) u. ( bday ` xR ) ) e. ( bday ` A ) <-> ( ( bday ` xL ) e. ( bday ` A ) /\ ( bday ` xR ) e. ( bday ` A ) ) ) : No typesetting found for |- ( ( ( bday ` xL ) u. ( bday ` xR ) ) e. ( bday ` A ) <-> ( ( bday ` xL ) e. ( bday ` A ) /\ ( bday ` xR ) e. ( bday ` A ) ) ) with typecode |- | 
						
							| 77 | 66 71 76 | sylanbrc | Could not format  ( ( ph /\ ( xR e. ( _Right ` A ) /\ xL e. ( _Left ` A ) ) ) -> ( ( bday ` xL ) u. ( bday ` xR ) ) e. ( bday ` A ) ) : No typesetting found for |- ( ( ph /\ ( xR e. ( _Right ` A ) /\ xL e. ( _Left ` A ) ) ) -> ( ( bday ` xL ) u. ( bday ` xR ) ) e. ( bday ` A ) ) with typecode |- | 
						
							| 78 |  | elun1 | Could not format  ( ( ( bday ` xL ) u. ( bday ` xR ) ) e. ( bday ` A ) -> ( ( bday ` xL ) u. ( bday ` xR ) ) e. ( ( bday ` A ) u. ( bday ` B ) ) ) : No typesetting found for |- ( ( ( bday ` xL ) u. ( bday ` xR ) ) e. ( bday ` A ) -> ( ( bday ` xL ) u. ( bday ` xR ) ) e. ( ( bday ` A ) u. ( bday ` B ) ) ) with typecode |- | 
						
							| 79 | 77 78 | syl | Could not format  ( ( ph /\ ( xR e. ( _Right ` A ) /\ xL e. ( _Left ` A ) ) ) -> ( ( bday ` xL ) u. ( bday ` xR ) ) e. ( ( bday ` A ) u. ( bday ` B ) ) ) : No typesetting found for |- ( ( ph /\ ( xR e. ( _Right ` A ) /\ xL e. ( _Left ` A ) ) ) -> ( ( bday ` xL ) u. ( bday ` xR ) ) e. ( ( bday ` A ) u. ( bday ` B ) ) ) with typecode |- | 
						
							| 80 | 57 59 62 79 | negsproplem1 | Could not format  ( ( ph /\ ( xR e. ( _Right ` A ) /\ xL e. ( _Left ` A ) ) ) -> ( ( -us ` xL ) e. No /\ ( xL  ( -us ` xR )  ( ( -us ` xL ) e. No /\ ( xL  ( -us ` xR ) 
						 | 
						
							| 81 | 80 | simprd | Could not format  ( ( ph /\ ( xR e. ( _Right ` A ) /\ xL e. ( _Left ` A ) ) ) -> ( xL  ( -us ` xR )  ( xL  ( -us ` xR ) 
						 | 
						
							| 82 | 56 81 | mpd | Could not format  ( ( ph /\ ( xR e. ( _Right ` A ) /\ xL e. ( _Left ` A ) ) ) -> ( -us ` xR )  ( -us ` xR ) 
						 | 
						
							| 83 |  | breq12 | Could not format  ( ( ( -us ` xR ) = a /\ ( -us ` xL ) = b ) -> ( ( -us ` xR )  a  ( ( -us ` xR )  a 
						 | 
						
							| 84 | 82 83 | syl5ibcom | Could not format  ( ( ph /\ ( xR e. ( _Right ` A ) /\ xL e. ( _Left ` A ) ) ) -> ( ( ( -us ` xR ) = a /\ ( -us ` xL ) = b ) -> a  ( ( ( -us ` xR ) = a /\ ( -us ` xL ) = b ) -> a 
						 | 
						
							| 85 | 84 | rexlimdvva | Could not format  ( ph -> ( E. xR e. ( _Right ` A ) E. xL e. ( _Left ` A ) ( ( -us ` xR ) = a /\ ( -us ` xL ) = b ) -> a  ( E. xR e. ( _Right ` A ) E. xL e. ( _Left ` A ) ( ( -us ` xR ) = a /\ ( -us ` xL ) = b ) -> a 
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							| 86 | 51 85 | biimtrid |  | 
						
							| 87 | 86 | 3impib |  | 
						
							| 88 | 8 11 38 42 87 | ssltd |  |