| Step | Hyp | Ref | Expression | 
						
							| 1 |  | atbtwn.b |  | 
						
							| 2 |  | atbtwn.l |  | 
						
							| 3 |  | atbtwn.j |  | 
						
							| 4 |  | atbtwn.a |  | 
						
							| 5 |  | simpr2 |  | 
						
							| 6 |  | simpr3 |  | 
						
							| 7 |  | nbrne2 |  | 
						
							| 8 | 5 6 7 | syl2anc |  | 
						
							| 9 | 2 3 4 | hlsupr |  | 
						
							| 10 | 8 9 | syldan |  | 
						
							| 11 |  | simp32 |  | 
						
							| 12 |  | simp31 |  | 
						
							| 13 |  | simp1l |  | 
						
							| 14 |  | simp2 |  | 
						
							| 15 |  | simp1r1 |  | 
						
							| 16 |  | simp1r2 |  | 
						
							| 17 |  | simp1r3 |  | 
						
							| 18 |  | simp33 |  | 
						
							| 19 | 1 2 3 4 | atbtwn |  | 
						
							| 20 | 13 14 15 16 17 18 19 | syl123anc |  | 
						
							| 21 | 12 20 | mpbid |  | 
						
							| 22 |  | simp1l1 |  | 
						
							| 23 |  | simp1l2 |  | 
						
							| 24 |  | simp1l3 |  | 
						
							| 25 | 2 3 4 | hlatexch2 |  | 
						
							| 26 | 22 14 23 24 11 25 | syl131anc |  | 
						
							| 27 | 18 26 | mpd |  | 
						
							| 28 | 3 4 | hlatjcom |  | 
						
							| 29 | 22 24 14 28 | syl3anc |  | 
						
							| 30 | 27 29 | breqtrrd |  | 
						
							| 31 | 11 21 30 | 3jca |  | 
						
							| 32 | 31 | 3exp |  | 
						
							| 33 | 32 | reximdvai |  | 
						
							| 34 | 10 33 | mpd |  |