| Step | Hyp | Ref | Expression | 
						
							| 1 |  | mstapst.p |  |-  P = ( mPreSt ` T ) | 
						
							| 2 |  | mstapst.s |  |-  S = ( mStat ` T ) | 
						
							| 3 |  | elmsta.v |  |-  V = ( mVars ` T ) | 
						
							| 4 |  | elmsta.z |  |-  Z = U. ( V " ( H u. { A } ) ) | 
						
							| 5 | 1 2 | mstapst |  |-  S C_ P | 
						
							| 6 | 5 | sseli |  |-  ( <. D , H , A >. e. S -> <. D , H , A >. e. P ) | 
						
							| 7 |  | eqid |  |-  ( mStRed ` T ) = ( mStRed ` T ) | 
						
							| 8 | 3 1 7 4 | msrval |  |-  ( <. D , H , A >. e. P -> ( ( mStRed ` T ) ` <. D , H , A >. ) = <. ( D i^i ( Z X. Z ) ) , H , A >. ) | 
						
							| 9 | 6 8 | syl |  |-  ( <. D , H , A >. e. S -> ( ( mStRed ` T ) ` <. D , H , A >. ) = <. ( D i^i ( Z X. Z ) ) , H , A >. ) | 
						
							| 10 | 7 2 | msrid |  |-  ( <. D , H , A >. e. S -> ( ( mStRed ` T ) ` <. D , H , A >. ) = <. D , H , A >. ) | 
						
							| 11 | 9 10 | eqtr3d |  |-  ( <. D , H , A >. e. S -> <. ( D i^i ( Z X. Z ) ) , H , A >. = <. D , H , A >. ) | 
						
							| 12 | 11 | fveq2d |  |-  ( <. D , H , A >. e. S -> ( 1st ` <. ( D i^i ( Z X. Z ) ) , H , A >. ) = ( 1st ` <. D , H , A >. ) ) | 
						
							| 13 | 12 | fveq2d |  |-  ( <. D , H , A >. e. S -> ( 1st ` ( 1st ` <. ( D i^i ( Z X. Z ) ) , H , A >. ) ) = ( 1st ` ( 1st ` <. D , H , A >. ) ) ) | 
						
							| 14 |  | inss1 |  |-  ( D i^i ( Z X. Z ) ) C_ D | 
						
							| 15 | 1 | mpstrcl |  |-  ( <. D , H , A >. e. P -> ( D e. _V /\ H e. _V /\ A e. _V ) ) | 
						
							| 16 | 6 15 | syl |  |-  ( <. D , H , A >. e. S -> ( D e. _V /\ H e. _V /\ A e. _V ) ) | 
						
							| 17 | 16 | simp1d |  |-  ( <. D , H , A >. e. S -> D e. _V ) | 
						
							| 18 |  | ssexg |  |-  ( ( ( D i^i ( Z X. Z ) ) C_ D /\ D e. _V ) -> ( D i^i ( Z X. Z ) ) e. _V ) | 
						
							| 19 | 14 17 18 | sylancr |  |-  ( <. D , H , A >. e. S -> ( D i^i ( Z X. Z ) ) e. _V ) | 
						
							| 20 | 16 | simp2d |  |-  ( <. D , H , A >. e. S -> H e. _V ) | 
						
							| 21 | 16 | simp3d |  |-  ( <. D , H , A >. e. S -> A e. _V ) | 
						
							| 22 |  | ot1stg |  |-  ( ( ( D i^i ( Z X. Z ) ) e. _V /\ H e. _V /\ A e. _V ) -> ( 1st ` ( 1st ` <. ( D i^i ( Z X. Z ) ) , H , A >. ) ) = ( D i^i ( Z X. Z ) ) ) | 
						
							| 23 | 19 20 21 22 | syl3anc |  |-  ( <. D , H , A >. e. S -> ( 1st ` ( 1st ` <. ( D i^i ( Z X. Z ) ) , H , A >. ) ) = ( D i^i ( Z X. Z ) ) ) | 
						
							| 24 |  | ot1stg |  |-  ( ( D e. _V /\ H e. _V /\ A e. _V ) -> ( 1st ` ( 1st ` <. D , H , A >. ) ) = D ) | 
						
							| 25 | 16 24 | syl |  |-  ( <. D , H , A >. e. S -> ( 1st ` ( 1st ` <. D , H , A >. ) ) = D ) | 
						
							| 26 | 13 23 25 | 3eqtr3d |  |-  ( <. D , H , A >. e. S -> ( D i^i ( Z X. Z ) ) = D ) | 
						
							| 27 |  | inss2 |  |-  ( D i^i ( Z X. Z ) ) C_ ( Z X. Z ) | 
						
							| 28 | 26 27 | eqsstrrdi |  |-  ( <. D , H , A >. e. S -> D C_ ( Z X. Z ) ) | 
						
							| 29 | 6 28 | jca |  |-  ( <. D , H , A >. e. S -> ( <. D , H , A >. e. P /\ D C_ ( Z X. Z ) ) ) | 
						
							| 30 | 8 | adantr |  |-  ( ( <. D , H , A >. e. P /\ D C_ ( Z X. Z ) ) -> ( ( mStRed ` T ) ` <. D , H , A >. ) = <. ( D i^i ( Z X. Z ) ) , H , A >. ) | 
						
							| 31 |  | simpr |  |-  ( ( <. D , H , A >. e. P /\ D C_ ( Z X. Z ) ) -> D C_ ( Z X. Z ) ) | 
						
							| 32 |  | dfss2 |  |-  ( D C_ ( Z X. Z ) <-> ( D i^i ( Z X. Z ) ) = D ) | 
						
							| 33 | 31 32 | sylib |  |-  ( ( <. D , H , A >. e. P /\ D C_ ( Z X. Z ) ) -> ( D i^i ( Z X. Z ) ) = D ) | 
						
							| 34 | 33 | oteq1d |  |-  ( ( <. D , H , A >. e. P /\ D C_ ( Z X. Z ) ) -> <. ( D i^i ( Z X. Z ) ) , H , A >. = <. D , H , A >. ) | 
						
							| 35 | 30 34 | eqtrd |  |-  ( ( <. D , H , A >. e. P /\ D C_ ( Z X. Z ) ) -> ( ( mStRed ` T ) ` <. D , H , A >. ) = <. D , H , A >. ) | 
						
							| 36 | 1 7 | msrf |  |-  ( mStRed ` T ) : P --> P | 
						
							| 37 |  | ffn |  |-  ( ( mStRed ` T ) : P --> P -> ( mStRed ` T ) Fn P ) | 
						
							| 38 | 36 37 | ax-mp |  |-  ( mStRed ` T ) Fn P | 
						
							| 39 |  | simpl |  |-  ( ( <. D , H , A >. e. P /\ D C_ ( Z X. Z ) ) -> <. D , H , A >. e. P ) | 
						
							| 40 |  | fnfvelrn |  |-  ( ( ( mStRed ` T ) Fn P /\ <. D , H , A >. e. P ) -> ( ( mStRed ` T ) ` <. D , H , A >. ) e. ran ( mStRed ` T ) ) | 
						
							| 41 | 38 39 40 | sylancr |  |-  ( ( <. D , H , A >. e. P /\ D C_ ( Z X. Z ) ) -> ( ( mStRed ` T ) ` <. D , H , A >. ) e. ran ( mStRed ` T ) ) | 
						
							| 42 | 35 41 | eqeltrrd |  |-  ( ( <. D , H , A >. e. P /\ D C_ ( Z X. Z ) ) -> <. D , H , A >. e. ran ( mStRed ` T ) ) | 
						
							| 43 | 7 2 | mstaval |  |-  S = ran ( mStRed ` T ) | 
						
							| 44 | 42 43 | eleqtrrdi |  |-  ( ( <. D , H , A >. e. P /\ D C_ ( Z X. Z ) ) -> <. D , H , A >. e. S ) | 
						
							| 45 | 29 44 | impbii |  |-  ( <. D , H , A >. e. S <-> ( <. D , H , A >. e. P /\ D C_ ( Z X. Z ) ) ) |