| Step | Hyp | Ref | Expression | 
						
							| 1 |  | lsatset.v |  | 
						
							| 2 |  | lsatset.n |  | 
						
							| 3 |  | lsatset.z |  | 
						
							| 4 |  | lsatset.a |  | 
						
							| 5 |  | elex |  | 
						
							| 6 |  | fveq2 |  | 
						
							| 7 | 6 1 | eqtr4di |  | 
						
							| 8 |  | fveq2 |  | 
						
							| 9 | 8 3 | eqtr4di |  | 
						
							| 10 | 9 | sneqd |  | 
						
							| 11 | 7 10 | difeq12d |  | 
						
							| 12 |  | fveq2 |  | 
						
							| 13 | 12 2 | eqtr4di |  | 
						
							| 14 | 13 | fveq1d |  | 
						
							| 15 | 11 14 | mpteq12dv |  | 
						
							| 16 | 15 | rneqd |  | 
						
							| 17 |  | df-lsatoms |  | 
						
							| 18 | 2 | fvexi |  | 
						
							| 19 | 18 | rnex |  | 
						
							| 20 |  | p0ex |  | 
						
							| 21 | 19 20 | unex |  | 
						
							| 22 |  | eqid |  | 
						
							| 23 |  | fvrn0 |  | 
						
							| 24 | 23 | a1i |  | 
						
							| 25 | 22 24 | fmpti |  | 
						
							| 26 |  | frn |  | 
						
							| 27 | 25 26 | ax-mp |  | 
						
							| 28 | 21 27 | ssexi |  | 
						
							| 29 | 16 17 28 | fvmpt |  | 
						
							| 30 | 5 29 | syl |  | 
						
							| 31 | 4 30 | eqtrid |  |