| Step | Hyp | Ref | Expression | 
						
							| 1 |  | prdsinvlem.y |  |-  Y = ( S Xs_ R ) | 
						
							| 2 |  | prdsinvlem.b |  |-  B = ( Base ` Y ) | 
						
							| 3 |  | prdsinvlem.p |  |-  .+ = ( +g ` Y ) | 
						
							| 4 |  | prdsinvlem.s |  |-  ( ph -> S e. V ) | 
						
							| 5 |  | prdsinvlem.i |  |-  ( ph -> I e. W ) | 
						
							| 6 |  | prdsinvlem.r |  |-  ( ph -> R : I --> Grp ) | 
						
							| 7 |  | prdsinvlem.f |  |-  ( ph -> F e. B ) | 
						
							| 8 |  | prdsinvlem.z |  |-  .0. = ( 0g o. R ) | 
						
							| 9 |  | prdsinvlem.n |  |-  N = ( y e. I |-> ( ( invg ` ( R ` y ) ) ` ( F ` y ) ) ) | 
						
							| 10 | 6 | ffvelcdmda |  |-  ( ( ph /\ y e. I ) -> ( R ` y ) e. Grp ) | 
						
							| 11 | 4 | adantr |  |-  ( ( ph /\ y e. I ) -> S e. V ) | 
						
							| 12 | 5 | adantr |  |-  ( ( ph /\ y e. I ) -> I e. W ) | 
						
							| 13 | 6 | ffnd |  |-  ( ph -> R Fn I ) | 
						
							| 14 | 13 | adantr |  |-  ( ( ph /\ y e. I ) -> R Fn I ) | 
						
							| 15 | 7 | adantr |  |-  ( ( ph /\ y e. I ) -> F e. B ) | 
						
							| 16 |  | simpr |  |-  ( ( ph /\ y e. I ) -> y e. I ) | 
						
							| 17 | 1 2 11 12 14 15 16 | prdsbasprj |  |-  ( ( ph /\ y e. I ) -> ( F ` y ) e. ( Base ` ( R ` y ) ) ) | 
						
							| 18 |  | eqid |  |-  ( Base ` ( R ` y ) ) = ( Base ` ( R ` y ) ) | 
						
							| 19 |  | eqid |  |-  ( invg ` ( R ` y ) ) = ( invg ` ( R ` y ) ) | 
						
							| 20 | 18 19 | grpinvcl |  |-  ( ( ( R ` y ) e. Grp /\ ( F ` y ) e. ( Base ` ( R ` y ) ) ) -> ( ( invg ` ( R ` y ) ) ` ( F ` y ) ) e. ( Base ` ( R ` y ) ) ) | 
						
							| 21 | 10 17 20 | syl2anc |  |-  ( ( ph /\ y e. I ) -> ( ( invg ` ( R ` y ) ) ` ( F ` y ) ) e. ( Base ` ( R ` y ) ) ) | 
						
							| 22 | 21 | ralrimiva |  |-  ( ph -> A. y e. I ( ( invg ` ( R ` y ) ) ` ( F ` y ) ) e. ( Base ` ( R ` y ) ) ) | 
						
							| 23 | 1 2 4 5 13 | prdsbasmpt |  |-  ( ph -> ( ( y e. I |-> ( ( invg ` ( R ` y ) ) ` ( F ` y ) ) ) e. B <-> A. y e. I ( ( invg ` ( R ` y ) ) ` ( F ` y ) ) e. ( Base ` ( R ` y ) ) ) ) | 
						
							| 24 | 22 23 | mpbird |  |-  ( ph -> ( y e. I |-> ( ( invg ` ( R ` y ) ) ` ( F ` y ) ) ) e. B ) | 
						
							| 25 | 9 24 | eqeltrid |  |-  ( ph -> N e. B ) | 
						
							| 26 | 6 | ffvelcdmda |  |-  ( ( ph /\ x e. I ) -> ( R ` x ) e. Grp ) | 
						
							| 27 | 4 | adantr |  |-  ( ( ph /\ x e. I ) -> S e. V ) | 
						
							| 28 | 5 | adantr |  |-  ( ( ph /\ x e. I ) -> I e. W ) | 
						
							| 29 | 13 | adantr |  |-  ( ( ph /\ x e. I ) -> R Fn I ) | 
						
							| 30 | 7 | adantr |  |-  ( ( ph /\ x e. I ) -> F e. B ) | 
						
							| 31 |  | simpr |  |-  ( ( ph /\ x e. I ) -> x e. I ) | 
						
							| 32 | 1 2 27 28 29 30 31 | prdsbasprj |  |-  ( ( ph /\ x e. I ) -> ( F ` x ) e. ( Base ` ( R ` x ) ) ) | 
						
							| 33 |  | eqid |  |-  ( Base ` ( R ` x ) ) = ( Base ` ( R ` x ) ) | 
						
							| 34 |  | eqid |  |-  ( +g ` ( R ` x ) ) = ( +g ` ( R ` x ) ) | 
						
							| 35 |  | eqid |  |-  ( 0g ` ( R ` x ) ) = ( 0g ` ( R ` x ) ) | 
						
							| 36 |  | eqid |  |-  ( invg ` ( R ` x ) ) = ( invg ` ( R ` x ) ) | 
						
							| 37 | 33 34 35 36 | grplinv |  |-  ( ( ( R ` x ) e. Grp /\ ( F ` x ) e. ( Base ` ( R ` x ) ) ) -> ( ( ( invg ` ( R ` x ) ) ` ( F ` x ) ) ( +g ` ( R ` x ) ) ( F ` x ) ) = ( 0g ` ( R ` x ) ) ) | 
						
							| 38 | 26 32 37 | syl2anc |  |-  ( ( ph /\ x e. I ) -> ( ( ( invg ` ( R ` x ) ) ` ( F ` x ) ) ( +g ` ( R ` x ) ) ( F ` x ) ) = ( 0g ` ( R ` x ) ) ) | 
						
							| 39 |  | 2fveq3 |  |-  ( y = x -> ( invg ` ( R ` y ) ) = ( invg ` ( R ` x ) ) ) | 
						
							| 40 |  | fveq2 |  |-  ( y = x -> ( F ` y ) = ( F ` x ) ) | 
						
							| 41 | 39 40 | fveq12d |  |-  ( y = x -> ( ( invg ` ( R ` y ) ) ` ( F ` y ) ) = ( ( invg ` ( R ` x ) ) ` ( F ` x ) ) ) | 
						
							| 42 |  | fvex |  |-  ( ( invg ` ( R ` x ) ) ` ( F ` x ) ) e. _V | 
						
							| 43 | 41 9 42 | fvmpt |  |-  ( x e. I -> ( N ` x ) = ( ( invg ` ( R ` x ) ) ` ( F ` x ) ) ) | 
						
							| 44 | 43 | adantl |  |-  ( ( ph /\ x e. I ) -> ( N ` x ) = ( ( invg ` ( R ` x ) ) ` ( F ` x ) ) ) | 
						
							| 45 | 44 | oveq1d |  |-  ( ( ph /\ x e. I ) -> ( ( N ` x ) ( +g ` ( R ` x ) ) ( F ` x ) ) = ( ( ( invg ` ( R ` x ) ) ` ( F ` x ) ) ( +g ` ( R ` x ) ) ( F ` x ) ) ) | 
						
							| 46 | 8 | fveq1i |  |-  ( .0. ` x ) = ( ( 0g o. R ) ` x ) | 
						
							| 47 |  | fvco2 |  |-  ( ( R Fn I /\ x e. I ) -> ( ( 0g o. R ) ` x ) = ( 0g ` ( R ` x ) ) ) | 
						
							| 48 | 13 47 | sylan |  |-  ( ( ph /\ x e. I ) -> ( ( 0g o. R ) ` x ) = ( 0g ` ( R ` x ) ) ) | 
						
							| 49 | 46 48 | eqtrid |  |-  ( ( ph /\ x e. I ) -> ( .0. ` x ) = ( 0g ` ( R ` x ) ) ) | 
						
							| 50 | 38 45 49 | 3eqtr4d |  |-  ( ( ph /\ x e. I ) -> ( ( N ` x ) ( +g ` ( R ` x ) ) ( F ` x ) ) = ( .0. ` x ) ) | 
						
							| 51 | 50 | mpteq2dva |  |-  ( ph -> ( x e. I |-> ( ( N ` x ) ( +g ` ( R ` x ) ) ( F ` x ) ) ) = ( x e. I |-> ( .0. ` x ) ) ) | 
						
							| 52 | 1 2 4 5 13 25 7 3 | prdsplusgval |  |-  ( ph -> ( N .+ F ) = ( x e. I |-> ( ( N ` x ) ( +g ` ( R ` x ) ) ( F ` x ) ) ) ) | 
						
							| 53 |  | fn0g |  |-  0g Fn _V | 
						
							| 54 |  | ssv |  |-  ran R C_ _V | 
						
							| 55 | 54 | a1i |  |-  ( ph -> ran R C_ _V ) | 
						
							| 56 |  | fnco |  |-  ( ( 0g Fn _V /\ R Fn I /\ ran R C_ _V ) -> ( 0g o. R ) Fn I ) | 
						
							| 57 | 53 13 55 56 | mp3an2i |  |-  ( ph -> ( 0g o. R ) Fn I ) | 
						
							| 58 | 8 | fneq1i |  |-  ( .0. Fn I <-> ( 0g o. R ) Fn I ) | 
						
							| 59 | 57 58 | sylibr |  |-  ( ph -> .0. Fn I ) | 
						
							| 60 |  | dffn5 |  |-  ( .0. Fn I <-> .0. = ( x e. I |-> ( .0. ` x ) ) ) | 
						
							| 61 | 59 60 | sylib |  |-  ( ph -> .0. = ( x e. I |-> ( .0. ` x ) ) ) | 
						
							| 62 | 51 52 61 | 3eqtr4d |  |-  ( ph -> ( N .+ F ) = .0. ) | 
						
							| 63 | 25 62 | jca |  |-  ( ph -> ( N e. B /\ ( N .+ F ) = .0. ) ) |