| Step | Hyp | Ref | Expression | 
						
							| 1 |  | negsproplem.1 |  | 
						
							| 2 |  | negsproplem4.1 |  | 
						
							| 3 |  | negsproplem4.2 |  | 
						
							| 4 |  | negsproplem4.3 |  | 
						
							| 5 |  | bdayelon |  | 
						
							| 6 | 5 | onordi |  | 
						
							| 7 |  | bdayelon |  | 
						
							| 8 | 7 | onordi |  | 
						
							| 9 |  | ordtri3or |  | 
						
							| 10 | 6 8 9 | mp2an |  | 
						
							| 11 | 1 | adantr |  | 
						
							| 12 | 2 | adantr |  | 
						
							| 13 | 3 | adantr |  | 
						
							| 14 | 4 | adantr |  | 
						
							| 15 |  | simpr |  | 
						
							| 16 | 11 12 13 14 15 | negsproplem4 |  | 
						
							| 17 | 16 | ex |  | 
						
							| 18 | 1 | adantr |  | 
						
							| 19 | 2 | adantr |  | 
						
							| 20 | 3 | adantr |  | 
						
							| 21 | 4 | adantr |  | 
						
							| 22 |  | simpr |  | 
						
							| 23 | 18 19 20 21 22 | negsproplem6 |  | 
						
							| 24 | 23 | ex |  | 
						
							| 25 | 1 | adantr |  | 
						
							| 26 | 2 | adantr |  | 
						
							| 27 | 3 | adantr |  | 
						
							| 28 | 4 | adantr |  | 
						
							| 29 |  | simpr |  | 
						
							| 30 | 25 26 27 28 29 | negsproplem5 |  | 
						
							| 31 | 30 | ex |  | 
						
							| 32 | 17 24 31 | 3jaod |  | 
						
							| 33 | 10 32 | mpi |  |