| Step | Hyp | Ref | Expression | 
						
							| 1 |  | ntrrn.x |  |-  X = U. J | 
						
							| 2 |  | ntrrn.i |  |-  I = ( int ` J ) | 
						
							| 3 | 2 | rneqi |  |-  ran I = ran ( int ` J ) | 
						
							| 4 |  | vpwex |  |-  ~P s e. _V | 
						
							| 5 | 4 | inex2 |  |-  ( J i^i ~P s ) e. _V | 
						
							| 6 | 5 | uniex |  |-  U. ( J i^i ~P s ) e. _V | 
						
							| 7 | 6 | rgenw |  |-  A. s e. ~P X U. ( J i^i ~P s ) e. _V | 
						
							| 8 |  | nfcv |  |-  F/_ s ~P X | 
						
							| 9 | 8 | fnmptf |  |-  ( A. s e. ~P X U. ( J i^i ~P s ) e. _V -> ( s e. ~P X |-> U. ( J i^i ~P s ) ) Fn ~P X ) | 
						
							| 10 | 7 9 | mp1i |  |-  ( J e. Top -> ( s e. ~P X |-> U. ( J i^i ~P s ) ) Fn ~P X ) | 
						
							| 11 | 1 | ntrfval |  |-  ( J e. Top -> ( int ` J ) = ( s e. ~P X |-> U. ( J i^i ~P s ) ) ) | 
						
							| 12 | 11 | fneq1d |  |-  ( J e. Top -> ( ( int ` J ) Fn ~P X <-> ( s e. ~P X |-> U. ( J i^i ~P s ) ) Fn ~P X ) ) | 
						
							| 13 | 10 12 | mpbird |  |-  ( J e. Top -> ( int ` J ) Fn ~P X ) | 
						
							| 14 |  | elpwi |  |-  ( s e. ~P X -> s C_ X ) | 
						
							| 15 | 1 | ntropn |  |-  ( ( J e. Top /\ s C_ X ) -> ( ( int ` J ) ` s ) e. J ) | 
						
							| 16 | 15 | ex |  |-  ( J e. Top -> ( s C_ X -> ( ( int ` J ) ` s ) e. J ) ) | 
						
							| 17 | 14 16 | syl5 |  |-  ( J e. Top -> ( s e. ~P X -> ( ( int ` J ) ` s ) e. J ) ) | 
						
							| 18 | 17 | ralrimiv |  |-  ( J e. Top -> A. s e. ~P X ( ( int ` J ) ` s ) e. J ) | 
						
							| 19 |  | fnfvrnss |  |-  ( ( ( int ` J ) Fn ~P X /\ A. s e. ~P X ( ( int ` J ) ` s ) e. J ) -> ran ( int ` J ) C_ J ) | 
						
							| 20 | 13 18 19 | syl2anc |  |-  ( J e. Top -> ran ( int ` J ) C_ J ) | 
						
							| 21 | 3 20 | eqsstrid |  |-  ( J e. Top -> ran I C_ J ) |