| Step | Hyp | Ref | Expression | 
						
							| 1 |  | scmatval.k |  |-  K = ( Base ` R ) | 
						
							| 2 |  | scmatval.a |  |-  A = ( N Mat R ) | 
						
							| 3 |  | scmatval.b |  |-  B = ( Base ` A ) | 
						
							| 4 |  | scmatval.1 |  |-  .1. = ( 1r ` A ) | 
						
							| 5 |  | scmatval.t |  |-  .x. = ( .s ` A ) | 
						
							| 6 |  | scmatval.s |  |-  S = ( N ScMat R ) | 
						
							| 7 |  | df-scmat |  |-  ScMat = ( n e. Fin , r e. _V |-> [_ ( n Mat r ) / a ]_ { m e. ( Base ` a ) | E. c e. ( Base ` r ) m = ( c ( .s ` a ) ( 1r ` a ) ) } ) | 
						
							| 8 | 7 | a1i |  |-  ( ( N e. Fin /\ R e. V ) -> ScMat = ( n e. Fin , r e. _V |-> [_ ( n Mat r ) / a ]_ { m e. ( Base ` a ) | E. c e. ( Base ` r ) m = ( c ( .s ` a ) ( 1r ` a ) ) } ) ) | 
						
							| 9 |  | ovexd |  |-  ( ( ( N e. Fin /\ R e. V ) /\ ( n = N /\ r = R ) ) -> ( n Mat r ) e. _V ) | 
						
							| 10 |  | fveq2 |  |-  ( a = ( n Mat r ) -> ( Base ` a ) = ( Base ` ( n Mat r ) ) ) | 
						
							| 11 |  | fveq2 |  |-  ( a = ( n Mat r ) -> ( .s ` a ) = ( .s ` ( n Mat r ) ) ) | 
						
							| 12 |  | eqidd |  |-  ( a = ( n Mat r ) -> c = c ) | 
						
							| 13 |  | fveq2 |  |-  ( a = ( n Mat r ) -> ( 1r ` a ) = ( 1r ` ( n Mat r ) ) ) | 
						
							| 14 | 11 12 13 | oveq123d |  |-  ( a = ( n Mat r ) -> ( c ( .s ` a ) ( 1r ` a ) ) = ( c ( .s ` ( n Mat r ) ) ( 1r ` ( n Mat r ) ) ) ) | 
						
							| 15 | 14 | eqeq2d |  |-  ( a = ( n Mat r ) -> ( m = ( c ( .s ` a ) ( 1r ` a ) ) <-> m = ( c ( .s ` ( n Mat r ) ) ( 1r ` ( n Mat r ) ) ) ) ) | 
						
							| 16 | 15 | rexbidv |  |-  ( a = ( n Mat r ) -> ( E. c e. ( Base ` r ) m = ( c ( .s ` a ) ( 1r ` a ) ) <-> E. c e. ( Base ` r ) m = ( c ( .s ` ( n Mat r ) ) ( 1r ` ( n Mat r ) ) ) ) ) | 
						
							| 17 | 10 16 | rabeqbidv |  |-  ( a = ( n Mat r ) -> { m e. ( Base ` a ) | E. c e. ( Base ` r ) m = ( c ( .s ` a ) ( 1r ` a ) ) } = { m e. ( Base ` ( n Mat r ) ) | E. c e. ( Base ` r ) m = ( c ( .s ` ( n Mat r ) ) ( 1r ` ( n Mat r ) ) ) } ) | 
						
							| 18 | 17 | adantl |  |-  ( ( ( ( N e. Fin /\ R e. V ) /\ ( n = N /\ r = R ) ) /\ a = ( n Mat r ) ) -> { m e. ( Base ` a ) | E. c e. ( Base ` r ) m = ( c ( .s ` a ) ( 1r ` a ) ) } = { m e. ( Base ` ( n Mat r ) ) | E. c e. ( Base ` r ) m = ( c ( .s ` ( n Mat r ) ) ( 1r ` ( n Mat r ) ) ) } ) | 
						
							| 19 | 9 18 | csbied |  |-  ( ( ( N e. Fin /\ R e. V ) /\ ( n = N /\ r = R ) ) -> [_ ( n Mat r ) / a ]_ { m e. ( Base ` a ) | E. c e. ( Base ` r ) m = ( c ( .s ` a ) ( 1r ` a ) ) } = { m e. ( Base ` ( n Mat r ) ) | E. c e. ( Base ` r ) m = ( c ( .s ` ( n Mat r ) ) ( 1r ` ( n Mat r ) ) ) } ) | 
						
							| 20 |  | oveq12 |  |-  ( ( n = N /\ r = R ) -> ( n Mat r ) = ( N Mat R ) ) | 
						
							| 21 | 20 | fveq2d |  |-  ( ( n = N /\ r = R ) -> ( Base ` ( n Mat r ) ) = ( Base ` ( N Mat R ) ) ) | 
						
							| 22 | 2 | fveq2i |  |-  ( Base ` A ) = ( Base ` ( N Mat R ) ) | 
						
							| 23 | 3 22 | eqtri |  |-  B = ( Base ` ( N Mat R ) ) | 
						
							| 24 | 21 23 | eqtr4di |  |-  ( ( n = N /\ r = R ) -> ( Base ` ( n Mat r ) ) = B ) | 
						
							| 25 |  | fveq2 |  |-  ( r = R -> ( Base ` r ) = ( Base ` R ) ) | 
						
							| 26 | 25 1 | eqtr4di |  |-  ( r = R -> ( Base ` r ) = K ) | 
						
							| 27 | 26 | adantl |  |-  ( ( n = N /\ r = R ) -> ( Base ` r ) = K ) | 
						
							| 28 | 20 | fveq2d |  |-  ( ( n = N /\ r = R ) -> ( .s ` ( n Mat r ) ) = ( .s ` ( N Mat R ) ) ) | 
						
							| 29 | 2 | fveq2i |  |-  ( .s ` A ) = ( .s ` ( N Mat R ) ) | 
						
							| 30 | 5 29 | eqtri |  |-  .x. = ( .s ` ( N Mat R ) ) | 
						
							| 31 | 28 30 | eqtr4di |  |-  ( ( n = N /\ r = R ) -> ( .s ` ( n Mat r ) ) = .x. ) | 
						
							| 32 |  | eqidd |  |-  ( ( n = N /\ r = R ) -> c = c ) | 
						
							| 33 | 20 | fveq2d |  |-  ( ( n = N /\ r = R ) -> ( 1r ` ( n Mat r ) ) = ( 1r ` ( N Mat R ) ) ) | 
						
							| 34 | 2 | fveq2i |  |-  ( 1r ` A ) = ( 1r ` ( N Mat R ) ) | 
						
							| 35 | 4 34 | eqtri |  |-  .1. = ( 1r ` ( N Mat R ) ) | 
						
							| 36 | 33 35 | eqtr4di |  |-  ( ( n = N /\ r = R ) -> ( 1r ` ( n Mat r ) ) = .1. ) | 
						
							| 37 | 31 32 36 | oveq123d |  |-  ( ( n = N /\ r = R ) -> ( c ( .s ` ( n Mat r ) ) ( 1r ` ( n Mat r ) ) ) = ( c .x. .1. ) ) | 
						
							| 38 | 37 | eqeq2d |  |-  ( ( n = N /\ r = R ) -> ( m = ( c ( .s ` ( n Mat r ) ) ( 1r ` ( n Mat r ) ) ) <-> m = ( c .x. .1. ) ) ) | 
						
							| 39 | 27 38 | rexeqbidv |  |-  ( ( n = N /\ r = R ) -> ( E. c e. ( Base ` r ) m = ( c ( .s ` ( n Mat r ) ) ( 1r ` ( n Mat r ) ) ) <-> E. c e. K m = ( c .x. .1. ) ) ) | 
						
							| 40 | 24 39 | rabeqbidv |  |-  ( ( n = N /\ r = R ) -> { m e. ( Base ` ( n Mat r ) ) | E. c e. ( Base ` r ) m = ( c ( .s ` ( n Mat r ) ) ( 1r ` ( n Mat r ) ) ) } = { m e. B | E. c e. K m = ( c .x. .1. ) } ) | 
						
							| 41 | 40 | adantl |  |-  ( ( ( N e. Fin /\ R e. V ) /\ ( n = N /\ r = R ) ) -> { m e. ( Base ` ( n Mat r ) ) | E. c e. ( Base ` r ) m = ( c ( .s ` ( n Mat r ) ) ( 1r ` ( n Mat r ) ) ) } = { m e. B | E. c e. K m = ( c .x. .1. ) } ) | 
						
							| 42 | 19 41 | eqtrd |  |-  ( ( ( N e. Fin /\ R e. V ) /\ ( n = N /\ r = R ) ) -> [_ ( n Mat r ) / a ]_ { m e. ( Base ` a ) | E. c e. ( Base ` r ) m = ( c ( .s ` a ) ( 1r ` a ) ) } = { m e. B | E. c e. K m = ( c .x. .1. ) } ) | 
						
							| 43 |  | simpl |  |-  ( ( N e. Fin /\ R e. V ) -> N e. Fin ) | 
						
							| 44 |  | elex |  |-  ( R e. V -> R e. _V ) | 
						
							| 45 | 44 | adantl |  |-  ( ( N e. Fin /\ R e. V ) -> R e. _V ) | 
						
							| 46 | 3 | fvexi |  |-  B e. _V | 
						
							| 47 | 46 | rabex |  |-  { m e. B | E. c e. K m = ( c .x. .1. ) } e. _V | 
						
							| 48 | 47 | a1i |  |-  ( ( N e. Fin /\ R e. V ) -> { m e. B | E. c e. K m = ( c .x. .1. ) } e. _V ) | 
						
							| 49 | 8 42 43 45 48 | ovmpod |  |-  ( ( N e. Fin /\ R e. V ) -> ( N ScMat R ) = { m e. B | E. c e. K m = ( c .x. .1. ) } ) | 
						
							| 50 | 6 49 | eqtrid |  |-  ( ( N e. Fin /\ R e. V ) -> S = { m e. B | E. c e. K m = ( c .x. .1. ) } ) |