| Step | Hyp | Ref | Expression | 
						
							| 1 |  | elnn0 |  |-  ( M e. NN0 <-> ( M e. NN \/ M = 0 ) ) | 
						
							| 2 |  | n0 |  |-  ( R =/= (/) <-> E. c c e. R ) | 
						
							| 3 |  | simpll |  |-  ( ( ( M e. NN /\ R e. V ) /\ c e. R ) -> M e. NN ) | 
						
							| 4 |  | simplr |  |-  ( ( ( M e. NN /\ R e. V ) /\ c e. R ) -> R e. V ) | 
						
							| 5 |  | 0nn0 |  |-  0 e. NN0 | 
						
							| 6 | 5 | fconst6 |  |-  ( R X. { 0 } ) : R --> NN0 | 
						
							| 7 | 6 | a1i |  |-  ( ( ( M e. NN /\ R e. V ) /\ c e. R ) -> ( R X. { 0 } ) : R --> NN0 ) | 
						
							| 8 |  | simpr |  |-  ( ( ( M e. NN /\ R e. V ) /\ c e. R ) -> c e. R ) | 
						
							| 9 |  | fvconst2g |  |-  ( ( 0 e. NN0 /\ c e. R ) -> ( ( R X. { 0 } ) ` c ) = 0 ) | 
						
							| 10 | 5 8 9 | sylancr |  |-  ( ( ( M e. NN /\ R e. V ) /\ c e. R ) -> ( ( R X. { 0 } ) ` c ) = 0 ) | 
						
							| 11 |  | ramz2 |  |-  ( ( ( M e. NN /\ R e. V /\ ( R X. { 0 } ) : R --> NN0 ) /\ ( c e. R /\ ( ( R X. { 0 } ) ` c ) = 0 ) ) -> ( M Ramsey ( R X. { 0 } ) ) = 0 ) | 
						
							| 12 | 3 4 7 8 10 11 | syl32anc |  |-  ( ( ( M e. NN /\ R e. V ) /\ c e. R ) -> ( M Ramsey ( R X. { 0 } ) ) = 0 ) | 
						
							| 13 | 12 | ex |  |-  ( ( M e. NN /\ R e. V ) -> ( c e. R -> ( M Ramsey ( R X. { 0 } ) ) = 0 ) ) | 
						
							| 14 | 13 | exlimdv |  |-  ( ( M e. NN /\ R e. V ) -> ( E. c c e. R -> ( M Ramsey ( R X. { 0 } ) ) = 0 ) ) | 
						
							| 15 | 2 14 | biimtrid |  |-  ( ( M e. NN /\ R e. V ) -> ( R =/= (/) -> ( M Ramsey ( R X. { 0 } ) ) = 0 ) ) | 
						
							| 16 | 15 | expimpd |  |-  ( M e. NN -> ( ( R e. V /\ R =/= (/) ) -> ( M Ramsey ( R X. { 0 } ) ) = 0 ) ) | 
						
							| 17 |  | simpl |  |-  ( ( R e. V /\ R =/= (/) ) -> R e. V ) | 
						
							| 18 |  | simpr |  |-  ( ( R e. V /\ R =/= (/) ) -> R =/= (/) ) | 
						
							| 19 | 6 | a1i |  |-  ( ( R e. V /\ R =/= (/) ) -> ( R X. { 0 } ) : R --> NN0 ) | 
						
							| 20 |  | 0z |  |-  0 e. ZZ | 
						
							| 21 |  | elsni |  |-  ( y e. { 0 } -> y = 0 ) | 
						
							| 22 |  | 0le0 |  |-  0 <_ 0 | 
						
							| 23 | 21 22 | eqbrtrdi |  |-  ( y e. { 0 } -> y <_ 0 ) | 
						
							| 24 | 23 | rgen |  |-  A. y e. { 0 } y <_ 0 | 
						
							| 25 |  | rnxp |  |-  ( R =/= (/) -> ran ( R X. { 0 } ) = { 0 } ) | 
						
							| 26 | 25 | adantl |  |-  ( ( R e. V /\ R =/= (/) ) -> ran ( R X. { 0 } ) = { 0 } ) | 
						
							| 27 | 26 | raleqdv |  |-  ( ( R e. V /\ R =/= (/) ) -> ( A. y e. ran ( R X. { 0 } ) y <_ 0 <-> A. y e. { 0 } y <_ 0 ) ) | 
						
							| 28 | 24 27 | mpbiri |  |-  ( ( R e. V /\ R =/= (/) ) -> A. y e. ran ( R X. { 0 } ) y <_ 0 ) | 
						
							| 29 |  | brralrspcev |  |-  ( ( 0 e. ZZ /\ A. y e. ran ( R X. { 0 } ) y <_ 0 ) -> E. x e. ZZ A. y e. ran ( R X. { 0 } ) y <_ x ) | 
						
							| 30 | 20 28 29 | sylancr |  |-  ( ( R e. V /\ R =/= (/) ) -> E. x e. ZZ A. y e. ran ( R X. { 0 } ) y <_ x ) | 
						
							| 31 |  | 0ram |  |-  ( ( ( R e. V /\ R =/= (/) /\ ( R X. { 0 } ) : R --> NN0 ) /\ E. x e. ZZ A. y e. ran ( R X. { 0 } ) y <_ x ) -> ( 0 Ramsey ( R X. { 0 } ) ) = sup ( ran ( R X. { 0 } ) , RR , < ) ) | 
						
							| 32 | 17 18 19 30 31 | syl31anc |  |-  ( ( R e. V /\ R =/= (/) ) -> ( 0 Ramsey ( R X. { 0 } ) ) = sup ( ran ( R X. { 0 } ) , RR , < ) ) | 
						
							| 33 | 26 | supeq1d |  |-  ( ( R e. V /\ R =/= (/) ) -> sup ( ran ( R X. { 0 } ) , RR , < ) = sup ( { 0 } , RR , < ) ) | 
						
							| 34 |  | ltso |  |-  < Or RR | 
						
							| 35 |  | 0re |  |-  0 e. RR | 
						
							| 36 |  | supsn |  |-  ( ( < Or RR /\ 0 e. RR ) -> sup ( { 0 } , RR , < ) = 0 ) | 
						
							| 37 | 34 35 36 | mp2an |  |-  sup ( { 0 } , RR , < ) = 0 | 
						
							| 38 | 37 | a1i |  |-  ( ( R e. V /\ R =/= (/) ) -> sup ( { 0 } , RR , < ) = 0 ) | 
						
							| 39 | 32 33 38 | 3eqtrd |  |-  ( ( R e. V /\ R =/= (/) ) -> ( 0 Ramsey ( R X. { 0 } ) ) = 0 ) | 
						
							| 40 |  | oveq1 |  |-  ( M = 0 -> ( M Ramsey ( R X. { 0 } ) ) = ( 0 Ramsey ( R X. { 0 } ) ) ) | 
						
							| 41 | 40 | eqeq1d |  |-  ( M = 0 -> ( ( M Ramsey ( R X. { 0 } ) ) = 0 <-> ( 0 Ramsey ( R X. { 0 } ) ) = 0 ) ) | 
						
							| 42 | 39 41 | imbitrrid |  |-  ( M = 0 -> ( ( R e. V /\ R =/= (/) ) -> ( M Ramsey ( R X. { 0 } ) ) = 0 ) ) | 
						
							| 43 | 16 42 | jaoi |  |-  ( ( M e. NN \/ M = 0 ) -> ( ( R e. V /\ R =/= (/) ) -> ( M Ramsey ( R X. { 0 } ) ) = 0 ) ) | 
						
							| 44 | 1 43 | sylbi |  |-  ( M e. NN0 -> ( ( R e. V /\ R =/= (/) ) -> ( M Ramsey ( R X. { 0 } ) ) = 0 ) ) | 
						
							| 45 | 44 | 3impib |  |-  ( ( M e. NN0 /\ R e. V /\ R =/= (/) ) -> ( M Ramsey ( R X. { 0 } ) ) = 0 ) |