| Step | Hyp | Ref | Expression | 
						
							| 1 |  | negsproplem.1 |  |-  ( ph -> 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 )  | 
						
							| 2 |  | negsproplem2.1 |  |-  ( ph -> A e. No ) | 
						
							| 3 |  | negsfn |  |-  -us Fn No | 
						
							| 4 |  | fnfun |  |-  ( -us Fn No -> Fun -us ) | 
						
							| 5 | 3 4 | ax-mp |  |-  Fun -us | 
						
							| 6 |  | fvex |  |-  ( _Right ` A ) e. _V | 
						
							| 7 | 6 | funimaex |  |-  ( Fun -us -> ( -us " ( _Right ` A ) ) e. _V ) | 
						
							| 8 | 5 7 | mp1i |  |-  ( ph -> ( -us " ( _Right ` A ) ) e. _V ) | 
						
							| 9 |  | fvex |  |-  ( _Left ` A ) e. _V | 
						
							| 10 | 9 | funimaex |  |-  ( Fun -us -> ( -us " ( _Left ` A ) ) e. _V ) | 
						
							| 11 | 5 10 | mp1i |  |-  ( ph -> ( -us " ( _Left ` A ) ) e. _V ) | 
						
							| 12 |  | rightssold |  |-  ( _Right ` A ) C_ ( _Old ` ( bday ` A ) ) | 
						
							| 13 |  | imass2 |  |-  ( ( _Right ` A ) C_ ( _Old ` ( bday ` A ) ) -> ( -us " ( _Right ` A ) ) C_ ( -us " ( _Old ` ( bday ` A ) ) ) ) | 
						
							| 14 | 12 13 | ax-mp |  |-  ( -us " ( _Right ` A ) ) C_ ( -us " ( _Old ` ( bday ` A ) ) ) | 
						
							| 15 | 1 | adantr |  |-  ( ( ph /\ a e. ( _Old ` ( bday ` 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 )  | 
						
							| 16 |  | oldssno |  |-  ( _Old ` ( bday ` A ) ) C_ No | 
						
							| 17 | 16 | sseli |  |-  ( a e. ( _Old ` ( bday ` A ) ) -> a e. No ) | 
						
							| 18 | 17 | adantl |  |-  ( ( ph /\ a e. ( _Old ` ( bday ` A ) ) ) -> a e. No ) | 
						
							| 19 |  | 0sno |  |-  0s e. No | 
						
							| 20 | 19 | a1i |  |-  ( ( ph /\ a e. ( _Old ` ( bday ` A ) ) ) -> 0s e. No ) | 
						
							| 21 |  | bday0s |  |-  ( bday ` 0s ) = (/) | 
						
							| 22 | 21 | uneq2i |  |-  ( ( bday ` a ) u. ( bday ` 0s ) ) = ( ( bday ` a ) u. (/) ) | 
						
							| 23 |  | un0 |  |-  ( ( bday ` a ) u. (/) ) = ( bday ` a ) | 
						
							| 24 | 22 23 | eqtri |  |-  ( ( bday ` a ) u. ( bday ` 0s ) ) = ( bday ` a ) | 
						
							| 25 |  | oldbdayim |  |-  ( a e. ( _Old ` ( bday ` A ) ) -> ( bday ` a ) e. ( bday ` A ) ) | 
						
							| 26 | 25 | adantl |  |-  ( ( ph /\ a e. ( _Old ` ( bday ` A ) ) ) -> ( bday ` a ) e. ( bday ` A ) ) | 
						
							| 27 |  | elun1 |  |-  ( ( bday ` a ) e. ( bday ` A ) -> ( bday ` a ) e. ( ( bday ` A ) u. ( bday ` B ) ) ) | 
						
							| 28 | 26 27 | syl |  |-  ( ( ph /\ a e. ( _Old ` ( bday ` A ) ) ) -> ( bday ` a ) e. ( ( bday ` A ) u. ( bday ` B ) ) ) | 
						
							| 29 | 24 28 | eqeltrid |  |-  ( ( ph /\ a e. ( _Old ` ( bday ` A ) ) ) -> ( ( bday ` a ) u. ( bday ` 0s ) ) e. ( ( bday ` A ) u. ( bday ` B ) ) ) | 
						
							| 30 | 15 18 20 29 | negsproplem1 |  |-  ( ( ph /\ a e. ( _Old ` ( bday ` A ) ) ) -> ( ( -us ` a ) e. No /\ ( a  ( -us ` 0s )  | 
						
							| 31 | 30 | simpld |  |-  ( ( ph /\ a e. ( _Old ` ( bday ` A ) ) ) -> ( -us ` a ) e. No ) | 
						
							| 32 | 31 | ralrimiva |  |-  ( ph -> A. a e. ( _Old ` ( bday ` A ) ) ( -us ` a ) e. No ) | 
						
							| 33 | 3 | fndmi |  |-  dom -us = No | 
						
							| 34 | 16 33 | sseqtrri |  |-  ( _Old ` ( bday ` A ) ) C_ dom -us | 
						
							| 35 |  | funimass4 |  |-  ( ( Fun -us /\ ( _Old ` ( bday ` A ) ) C_ dom -us ) -> ( ( -us " ( _Old ` ( bday ` A ) ) ) C_ No <-> A. a e. ( _Old ` ( bday ` A ) ) ( -us ` a ) e. No ) ) | 
						
							| 36 | 5 34 35 | mp2an |  |-  ( ( -us " ( _Old ` ( bday ` A ) ) ) C_ No <-> A. a e. ( _Old ` ( bday ` A ) ) ( -us ` a ) e. No ) | 
						
							| 37 | 32 36 | sylibr |  |-  ( ph -> ( -us " ( _Old ` ( bday ` A ) ) ) C_ No ) | 
						
							| 38 | 14 37 | sstrid |  |-  ( ph -> ( -us " ( _Right ` A ) ) C_ No ) | 
						
							| 39 |  | leftssold |  |-  ( _Left ` A ) C_ ( _Old ` ( bday ` A ) ) | 
						
							| 40 |  | imass2 |  |-  ( ( _Left ` A ) C_ ( _Old ` ( bday ` A ) ) -> ( -us " ( _Left ` A ) ) C_ ( -us " ( _Old ` ( bday ` A ) ) ) ) | 
						
							| 41 | 39 40 | ax-mp |  |-  ( -us " ( _Left ` A ) ) C_ ( -us " ( _Old ` ( bday ` A ) ) ) | 
						
							| 42 | 41 37 | sstrid |  |-  ( ph -> ( -us " ( _Left ` A ) ) C_ No ) | 
						
							| 43 |  | rightssno |  |-  ( _Right ` A ) C_ No | 
						
							| 44 |  | fvelimab |  |-  ( ( -us Fn No /\ ( _Right ` A ) C_ No ) -> ( a e. ( -us " ( _Right ` A ) ) <-> E. xR e. ( _Right ` A ) ( -us ` xR ) = a ) ) | 
						
							| 45 | 3 43 44 | mp2an |  |-  ( a e. ( -us " ( _Right ` A ) ) <-> E. xR e. ( _Right ` A ) ( -us ` xR ) = a ) | 
						
							| 46 |  | leftssno |  |-  ( _Left ` A ) C_ No | 
						
							| 47 |  | fvelimab |  |-  ( ( -us Fn No /\ ( _Left ` A ) C_ No ) -> ( b e. ( -us " ( _Left ` A ) ) <-> E. xL e. ( _Left ` A ) ( -us ` xL ) = b ) ) | 
						
							| 48 | 3 46 47 | mp2an |  |-  ( b e. ( -us " ( _Left ` A ) ) <-> E. xL e. ( _Left ` A ) ( -us ` xL ) = b ) | 
						
							| 49 | 45 48 | anbi12i |  |-  ( ( 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 ) ) | 
						
							| 50 |  | reeanv |  |-  ( 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 ) ) | 
						
							| 51 | 49 50 | bitr4i |  |-  ( ( 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 ) ) | 
						
							| 52 |  | lltropt |  |-  ( _Left ` A ) < | 
						
							| 53 | 52 | a1i |  |-  ( ( ph /\ ( xR e. ( _Right ` A ) /\ xL e. ( _Left ` A ) ) ) -> ( _Left ` A ) < | 
						
							| 54 |  | simprr |  |-  ( ( ph /\ ( xR e. ( _Right ` A ) /\ xL e. ( _Left ` A ) ) ) -> xL e. ( _Left ` A ) ) | 
						
							| 55 |  | simprl |  |-  ( ( ph /\ ( xR e. ( _Right ` A ) /\ xL e. ( _Left ` A ) ) ) -> xR e. ( _Right ` A ) ) | 
						
							| 56 | 53 54 55 | ssltsepcd |  |-  ( ( ph /\ ( xR e. ( _Right ` A ) /\ xL e. ( _Left ` A ) ) ) -> xL  | 
						
							| 57 | 1 | adantr |  |-  ( ( 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 )  | 
						
							| 58 | 46 | sseli |  |-  ( xL e. ( _Left ` A ) -> xL e. No ) | 
						
							| 59 | 58 | ad2antll |  |-  ( ( ph /\ ( xR e. ( _Right ` A ) /\ xL e. ( _Left ` A ) ) ) -> xL e. No ) | 
						
							| 60 | 43 | sseli |  |-  ( xR e. ( _Right ` A ) -> xR e. No ) | 
						
							| 61 | 60 | adantr |  |-  ( ( xR e. ( _Right ` A ) /\ xL e. ( _Left ` A ) ) -> xR e. No ) | 
						
							| 62 | 61 | adantl |  |-  ( ( ph /\ ( xR e. ( _Right ` A ) /\ xL e. ( _Left ` A ) ) ) -> xR e. No ) | 
						
							| 63 | 39 | sseli |  |-  ( xL e. ( _Left ` A ) -> xL e. ( _Old ` ( bday ` A ) ) ) | 
						
							| 64 | 63 | ad2antll |  |-  ( ( ph /\ ( xR e. ( _Right ` A ) /\ xL e. ( _Left ` A ) ) ) -> xL e. ( _Old ` ( bday ` A ) ) ) | 
						
							| 65 |  | oldbdayim |  |-  ( xL e. ( _Old ` ( bday ` A ) ) -> ( bday ` xL ) e. ( bday ` A ) ) | 
						
							| 66 | 64 65 | syl |  |-  ( ( ph /\ ( xR e. ( _Right ` A ) /\ xL e. ( _Left ` A ) ) ) -> ( bday ` xL ) e. ( bday ` A ) ) | 
						
							| 67 | 12 | a1i |  |-  ( ph -> ( _Right ` A ) C_ ( _Old ` ( bday ` A ) ) ) | 
						
							| 68 | 67 | sselda |  |-  ( ( ph /\ xR e. ( _Right ` A ) ) -> xR e. ( _Old ` ( bday ` A ) ) ) | 
						
							| 69 | 68 | adantrr |  |-  ( ( ph /\ ( xR e. ( _Right ` A ) /\ xL e. ( _Left ` A ) ) ) -> xR e. ( _Old ` ( bday ` A ) ) ) | 
						
							| 70 |  | oldbdayim |  |-  ( xR e. ( _Old ` ( bday ` A ) ) -> ( bday ` xR ) e. ( bday ` A ) ) | 
						
							| 71 | 69 70 | syl |  |-  ( ( ph /\ ( xR e. ( _Right ` A ) /\ xL e. ( _Left ` A ) ) ) -> ( bday ` xR ) e. ( bday ` A ) ) | 
						
							| 72 |  | bdayelon |  |-  ( bday ` xL ) e. On | 
						
							| 73 |  | bdayelon |  |-  ( bday ` xR ) e. On | 
						
							| 74 |  | bdayelon |  |-  ( bday ` A ) e. On | 
						
							| 75 |  | onunel |  |-  ( ( ( 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 ) ) ) ) | 
						
							| 76 | 72 73 74 75 | mp3an |  |-  ( ( ( bday ` xL ) u. ( bday ` xR ) ) e. ( bday ` A ) <-> ( ( bday ` xL ) e. ( bday ` A ) /\ ( bday ` xR ) e. ( bday ` A ) ) ) | 
						
							| 77 | 66 71 76 | sylanbrc |  |-  ( ( ph /\ ( xR e. ( _Right ` A ) /\ xL e. ( _Left ` A ) ) ) -> ( ( bday ` xL ) u. ( bday ` xR ) ) e. ( bday ` A ) ) | 
						
							| 78 |  | elun1 |  |-  ( ( ( bday ` xL ) u. ( bday ` xR ) ) e. ( bday ` A ) -> ( ( bday ` xL ) u. ( bday ` xR ) ) e. ( ( bday ` A ) u. ( bday ` B ) ) ) | 
						
							| 79 | 77 78 | syl |  |-  ( ( ph /\ ( xR e. ( _Right ` A ) /\ xL e. ( _Left ` A ) ) ) -> ( ( bday ` xL ) u. ( bday ` xR ) ) e. ( ( bday ` A ) u. ( bday ` B ) ) ) | 
						
							| 80 | 57 59 62 79 | negsproplem1 |  |-  ( ( ph /\ ( xR e. ( _Right ` A ) /\ xL e. ( _Left ` A ) ) ) -> ( ( -us ` xL ) e. No /\ ( xL  ( -us ` xR )  | 
						
							| 81 | 80 | simprd |  |-  ( ( ph /\ ( xR e. ( _Right ` A ) /\ xL e. ( _Left ` A ) ) ) -> ( xL  ( -us ` xR )  | 
						
							| 82 | 56 81 | mpd |  |-  ( ( ph /\ ( xR e. ( _Right ` A ) /\ xL e. ( _Left ` A ) ) ) -> ( -us ` xR )  | 
						
							| 83 |  | breq12 |  |-  ( ( ( -us ` xR ) = a /\ ( -us ` xL ) = b ) -> ( ( -us ` xR )  a  | 
						
							| 84 | 82 83 | syl5ibcom |  |-  ( ( ph /\ ( xR e. ( _Right ` A ) /\ xL e. ( _Left ` A ) ) ) -> ( ( ( -us ` xR ) = a /\ ( -us ` xL ) = b ) -> a  | 
						
							| 85 | 84 | rexlimdvva |  |-  ( ph -> ( E. xR e. ( _Right ` A ) E. xL e. ( _Left ` A ) ( ( -us ` xR ) = a /\ ( -us ` xL ) = b ) -> a  | 
						
							| 86 | 51 85 | biimtrid |  |-  ( ph -> ( ( a e. ( -us " ( _Right ` A ) ) /\ b e. ( -us " ( _Left ` A ) ) ) -> a  | 
						
							| 87 | 86 | 3impib |  |-  ( ( ph /\ a e. ( -us " ( _Right ` A ) ) /\ b e. ( -us " ( _Left ` A ) ) ) -> a  | 
						
							| 88 | 8 11 38 42 87 | ssltd |  |-  ( ph -> ( -us " ( _Right ` A ) ) < |