| Step | 
						Hyp | 
						Ref | 
						Expression | 
					
						
							| 1 | 
							
								
							 | 
							peano2 | 
							 |-  ( N e. _om -> suc N e. _om )  | 
						
						
							| 2 | 
							
								
							 | 
							ovexd | 
							 |-  ( N e. _om -> ( a |g b ) e. _V )  | 
						
						
							| 3 | 
							
								
							 | 
							isfmlasuc | 
							 |-  ( ( suc N e. _om /\ ( a |g b ) e. _V ) -> ( ( a |g b ) e. ( Fmla ` suc suc N ) <-> ( ( a |g b ) e. ( Fmla ` suc N ) \/ E. u e. ( Fmla ` suc N ) ( E. v e. ( Fmla ` suc N ) ( a |g b ) = ( u |g v ) \/ E. i e. _om ( a |g b ) = A.g i u ) ) ) )  | 
						
						
							| 4 | 
							
								1 2 3
							 | 
							syl2anc | 
							 |-  ( N e. _om -> ( ( a |g b ) e. ( Fmla ` suc suc N ) <-> ( ( a |g b ) e. ( Fmla ` suc N ) \/ E. u e. ( Fmla ` suc N ) ( E. v e. ( Fmla ` suc N ) ( a |g b ) = ( u |g v ) \/ E. i e. _om ( a |g b ) = A.g i u ) ) ) )  | 
						
						
							| 5 | 
							
								4
							 | 
							adantr | 
							 |-  ( ( N e. _om /\ ( ( a |g b ) e. ( Fmla ` suc N ) -> ( a e. ( Fmla ` suc N ) /\ b e. ( Fmla ` suc N ) ) ) ) -> ( ( a |g b ) e. ( Fmla ` suc suc N ) <-> ( ( a |g b ) e. ( Fmla ` suc N ) \/ E. u e. ( Fmla ` suc N ) ( E. v e. ( Fmla ` suc N ) ( a |g b ) = ( u |g v ) \/ E. i e. _om ( a |g b ) = A.g i u ) ) ) )  | 
						
						
							| 6 | 
							
								
							 | 
							fmlasssuc | 
							 |-  ( suc N e. _om -> ( Fmla ` suc N ) C_ ( Fmla ` suc suc N ) )  | 
						
						
							| 7 | 
							
								1 6
							 | 
							syl | 
							 |-  ( N e. _om -> ( Fmla ` suc N ) C_ ( Fmla ` suc suc N ) )  | 
						
						
							| 8 | 
							
								7
							 | 
							sseld | 
							 |-  ( N e. _om -> ( a e. ( Fmla ` suc N ) -> a e. ( Fmla ` suc suc N ) ) )  | 
						
						
							| 9 | 
							
								7
							 | 
							sseld | 
							 |-  ( N e. _om -> ( b e. ( Fmla ` suc N ) -> b e. ( Fmla ` suc suc N ) ) )  | 
						
						
							| 10 | 
							
								8 9
							 | 
							anim12d | 
							 |-  ( N e. _om -> ( ( a e. ( Fmla ` suc N ) /\ b e. ( Fmla ` suc N ) ) -> ( a e. ( Fmla ` suc suc N ) /\ b e. ( Fmla ` suc suc N ) ) ) )  | 
						
						
							| 11 | 
							
								10
							 | 
							com12 | 
							 |-  ( ( a e. ( Fmla ` suc N ) /\ b e. ( Fmla ` suc N ) ) -> ( N e. _om -> ( a e. ( Fmla ` suc suc N ) /\ b e. ( Fmla ` suc suc N ) ) ) )  | 
						
						
							| 12 | 
							
								11
							 | 
							imim2i | 
							 |-  ( ( ( a |g b ) e. ( Fmla ` suc N ) -> ( a e. ( Fmla ` suc N ) /\ b e. ( Fmla ` suc N ) ) ) -> ( ( a |g b ) e. ( Fmla ` suc N ) -> ( N e. _om -> ( a e. ( Fmla ` suc suc N ) /\ b e. ( Fmla ` suc suc N ) ) ) ) )  | 
						
						
							| 13 | 
							
								12
							 | 
							com23 | 
							 |-  ( ( ( a |g b ) e. ( Fmla ` suc N ) -> ( a e. ( Fmla ` suc N ) /\ b e. ( Fmla ` suc N ) ) ) -> ( N e. _om -> ( ( a |g b ) e. ( Fmla ` suc N ) -> ( a e. ( Fmla ` suc suc N ) /\ b e. ( Fmla ` suc suc N ) ) ) ) )  | 
						
						
							| 14 | 
							
								13
							 | 
							impcom | 
							 |-  ( ( N e. _om /\ ( ( a |g b ) e. ( Fmla ` suc N ) -> ( a e. ( Fmla ` suc N ) /\ b e. ( Fmla ` suc N ) ) ) ) -> ( ( a |g b ) e. ( Fmla ` suc N ) -> ( a e. ( Fmla ` suc suc N ) /\ b e. ( Fmla ` suc suc N ) ) ) )  | 
						
						
							| 15 | 
							
								
							 | 
							gonafv | 
							 |-  ( ( a e. _V /\ b e. _V ) -> ( a |g b ) = <. 1o , <. a , b >. >. )  | 
						
						
							| 16 | 
							
								15
							 | 
							el2v | 
							 |-  ( a |g b ) = <. 1o , <. a , b >. >.  | 
						
						
							| 17 | 
							
								16
							 | 
							a1i | 
							 |-  ( ( u e. ( Fmla ` suc N ) /\ v e. ( Fmla ` suc N ) ) -> ( a |g b ) = <. 1o , <. a , b >. >. )  | 
						
						
							| 18 | 
							
								
							 | 
							gonafv | 
							 |-  ( ( u e. ( Fmla ` suc N ) /\ v e. ( Fmla ` suc N ) ) -> ( u |g v ) = <. 1o , <. u , v >. >. )  | 
						
						
							| 19 | 
							
								17 18
							 | 
							eqeq12d | 
							 |-  ( ( u e. ( Fmla ` suc N ) /\ v e. ( Fmla ` suc N ) ) -> ( ( a |g b ) = ( u |g v ) <-> <. 1o , <. a , b >. >. = <. 1o , <. u , v >. >. ) )  | 
						
						
							| 20 | 
							
								
							 | 
							1oex | 
							 |-  1o e. _V  | 
						
						
							| 21 | 
							
								
							 | 
							opex | 
							 |-  <. a , b >. e. _V  | 
						
						
							| 22 | 
							
								20 21
							 | 
							opth | 
							 |-  ( <. 1o , <. a , b >. >. = <. 1o , <. u , v >. >. <-> ( 1o = 1o /\ <. a , b >. = <. u , v >. ) )  | 
						
						
							| 23 | 
							
								19 22
							 | 
							bitrdi | 
							 |-  ( ( u e. ( Fmla ` suc N ) /\ v e. ( Fmla ` suc N ) ) -> ( ( a |g b ) = ( u |g v ) <-> ( 1o = 1o /\ <. a , b >. = <. u , v >. ) ) )  | 
						
						
							| 24 | 
							
								23
							 | 
							adantll | 
							 |-  ( ( ( N e. _om /\ u e. ( Fmla ` suc N ) ) /\ v e. ( Fmla ` suc N ) ) -> ( ( a |g b ) = ( u |g v ) <-> ( 1o = 1o /\ <. a , b >. = <. u , v >. ) ) )  | 
						
						
							| 25 | 
							
								
							 | 
							vex | 
							 |-  a e. _V  | 
						
						
							| 26 | 
							
								
							 | 
							vex | 
							 |-  b e. _V  | 
						
						
							| 27 | 
							
								25 26
							 | 
							opth | 
							 |-  ( <. a , b >. = <. u , v >. <-> ( a = u /\ b = v ) )  | 
						
						
							| 28 | 
							
								
							 | 
							eleq1w | 
							 |-  ( u = a -> ( u e. ( Fmla ` suc N ) <-> a e. ( Fmla ` suc N ) ) )  | 
						
						
							| 29 | 
							
								28
							 | 
							equcoms | 
							 |-  ( a = u -> ( u e. ( Fmla ` suc N ) <-> a e. ( Fmla ` suc N ) ) )  | 
						
						
							| 30 | 
							
								
							 | 
							eleq1w | 
							 |-  ( v = b -> ( v e. ( Fmla ` suc N ) <-> b e. ( Fmla ` suc N ) ) )  | 
						
						
							| 31 | 
							
								30
							 | 
							equcoms | 
							 |-  ( b = v -> ( v e. ( Fmla ` suc N ) <-> b e. ( Fmla ` suc N ) ) )  | 
						
						
							| 32 | 
							
								29 31
							 | 
							bi2anan9 | 
							 |-  ( ( a = u /\ b = v ) -> ( ( u e. ( Fmla ` suc N ) /\ v e. ( Fmla ` suc N ) ) <-> ( a e. ( Fmla ` suc N ) /\ b e. ( Fmla ` suc N ) ) ) )  | 
						
						
							| 33 | 
							
								32 11
							 | 
							biimtrdi | 
							 |-  ( ( a = u /\ b = v ) -> ( ( u e. ( Fmla ` suc N ) /\ v e. ( Fmla ` suc N ) ) -> ( N e. _om -> ( a e. ( Fmla ` suc suc N ) /\ b e. ( Fmla ` suc suc N ) ) ) ) )  | 
						
						
							| 34 | 
							
								27 33
							 | 
							sylbi | 
							 |-  ( <. a , b >. = <. u , v >. -> ( ( u e. ( Fmla ` suc N ) /\ v e. ( Fmla ` suc N ) ) -> ( N e. _om -> ( a e. ( Fmla ` suc suc N ) /\ b e. ( Fmla ` suc suc N ) ) ) ) )  | 
						
						
							| 35 | 
							
								34
							 | 
							adantl | 
							 |-  ( ( 1o = 1o /\ <. a , b >. = <. u , v >. ) -> ( ( u e. ( Fmla ` suc N ) /\ v e. ( Fmla ` suc N ) ) -> ( N e. _om -> ( a e. ( Fmla ` suc suc N ) /\ b e. ( Fmla ` suc suc N ) ) ) ) )  | 
						
						
							| 36 | 
							
								35
							 | 
							com13 | 
							 |-  ( N e. _om -> ( ( u e. ( Fmla ` suc N ) /\ v e. ( Fmla ` suc N ) ) -> ( ( 1o = 1o /\ <. a , b >. = <. u , v >. ) -> ( a e. ( Fmla ` suc suc N ) /\ b e. ( Fmla ` suc suc N ) ) ) ) )  | 
						
						
							| 37 | 
							
								36
							 | 
							impl | 
							 |-  ( ( ( N e. _om /\ u e. ( Fmla ` suc N ) ) /\ v e. ( Fmla ` suc N ) ) -> ( ( 1o = 1o /\ <. a , b >. = <. u , v >. ) -> ( a e. ( Fmla ` suc suc N ) /\ b e. ( Fmla ` suc suc N ) ) ) )  | 
						
						
							| 38 | 
							
								24 37
							 | 
							sylbid | 
							 |-  ( ( ( N e. _om /\ u e. ( Fmla ` suc N ) ) /\ v e. ( Fmla ` suc N ) ) -> ( ( a |g b ) = ( u |g v ) -> ( a e. ( Fmla ` suc suc N ) /\ b e. ( Fmla ` suc suc N ) ) ) )  | 
						
						
							| 39 | 
							
								38
							 | 
							rexlimdva | 
							 |-  ( ( N e. _om /\ u e. ( Fmla ` suc N ) ) -> ( E. v e. ( Fmla ` suc N ) ( a |g b ) = ( u |g v ) -> ( a e. ( Fmla ` suc suc N ) /\ b e. ( Fmla ` suc suc N ) ) ) )  | 
						
						
							| 40 | 
							
								
							 | 
							gonanegoal | 
							 |-  ( a |g b ) =/= A.g i u  | 
						
						
							| 41 | 
							
								
							 | 
							eqneqall | 
							 |-  ( ( a |g b ) = A.g i u -> ( ( a |g b ) =/= A.g i u -> ( a e. ( Fmla ` suc suc N ) /\ b e. ( Fmla ` suc suc N ) ) ) )  | 
						
						
							| 42 | 
							
								40 41
							 | 
							mpi | 
							 |-  ( ( a |g b ) = A.g i u -> ( a e. ( Fmla ` suc suc N ) /\ b e. ( Fmla ` suc suc N ) ) )  | 
						
						
							| 43 | 
							
								42
							 | 
							a1i | 
							 |-  ( ( ( N e. _om /\ u e. ( Fmla ` suc N ) ) /\ i e. _om ) -> ( ( a |g b ) = A.g i u -> ( a e. ( Fmla ` suc suc N ) /\ b e. ( Fmla ` suc suc N ) ) ) )  | 
						
						
							| 44 | 
							
								43
							 | 
							rexlimdva | 
							 |-  ( ( N e. _om /\ u e. ( Fmla ` suc N ) ) -> ( E. i e. _om ( a |g b ) = A.g i u -> ( a e. ( Fmla ` suc suc N ) /\ b e. ( Fmla ` suc suc N ) ) ) )  | 
						
						
							| 45 | 
							
								39 44
							 | 
							jaod | 
							 |-  ( ( N e. _om /\ u e. ( Fmla ` suc N ) ) -> ( ( E. v e. ( Fmla ` suc N ) ( a |g b ) = ( u |g v ) \/ E. i e. _om ( a |g b ) = A.g i u ) -> ( a e. ( Fmla ` suc suc N ) /\ b e. ( Fmla ` suc suc N ) ) ) )  | 
						
						
							| 46 | 
							
								45
							 | 
							rexlimdva | 
							 |-  ( N e. _om -> ( E. u e. ( Fmla ` suc N ) ( E. v e. ( Fmla ` suc N ) ( a |g b ) = ( u |g v ) \/ E. i e. _om ( a |g b ) = A.g i u ) -> ( a e. ( Fmla ` suc suc N ) /\ b e. ( Fmla ` suc suc N ) ) ) )  | 
						
						
							| 47 | 
							
								46
							 | 
							adantr | 
							 |-  ( ( N e. _om /\ ( ( a |g b ) e. ( Fmla ` suc N ) -> ( a e. ( Fmla ` suc N ) /\ b e. ( Fmla ` suc N ) ) ) ) -> ( E. u e. ( Fmla ` suc N ) ( E. v e. ( Fmla ` suc N ) ( a |g b ) = ( u |g v ) \/ E. i e. _om ( a |g b ) = A.g i u ) -> ( a e. ( Fmla ` suc suc N ) /\ b e. ( Fmla ` suc suc N ) ) ) )  | 
						
						
							| 48 | 
							
								14 47
							 | 
							jaod | 
							 |-  ( ( N e. _om /\ ( ( a |g b ) e. ( Fmla ` suc N ) -> ( a e. ( Fmla ` suc N ) /\ b e. ( Fmla ` suc N ) ) ) ) -> ( ( ( a |g b ) e. ( Fmla ` suc N ) \/ E. u e. ( Fmla ` suc N ) ( E. v e. ( Fmla ` suc N ) ( a |g b ) = ( u |g v ) \/ E. i e. _om ( a |g b ) = A.g i u ) ) -> ( a e. ( Fmla ` suc suc N ) /\ b e. ( Fmla ` suc suc N ) ) ) )  | 
						
						
							| 49 | 
							
								5 48
							 | 
							sylbid | 
							 |-  ( ( N e. _om /\ ( ( a |g b ) e. ( Fmla ` suc N ) -> ( a e. ( Fmla ` suc N ) /\ b e. ( Fmla ` suc N ) ) ) ) -> ( ( a |g b ) e. ( Fmla ` suc suc N ) -> ( a e. ( Fmla ` suc suc N ) /\ b e. ( Fmla ` suc suc N ) ) ) )  | 
						
						
							| 50 | 
							
								49
							 | 
							ex | 
							 |-  ( N e. _om -> ( ( ( a |g b ) e. ( Fmla ` suc N ) -> ( a e. ( Fmla ` suc N ) /\ b e. ( Fmla ` suc N ) ) ) -> ( ( a |g b ) e. ( Fmla ` suc suc N ) -> ( a e. ( Fmla ` suc suc N ) /\ b e. ( Fmla ` suc suc N ) ) ) ) )  |