| Step | Hyp | Ref | Expression | 
						
							| 1 |  | lencl |  | 
						
							| 2 |  | nn0cn |  | 
						
							| 3 |  | peano2cnm |  | 
						
							| 4 | 3 | subid1d |  | 
						
							| 5 | 4 | oveq1d |  | 
						
							| 6 |  | sub1m1 |  | 
						
							| 7 | 5 6 | eqtrd |  | 
						
							| 8 | 1 2 7 | 3syl |  | 
						
							| 9 | 8 | adantr |  | 
						
							| 10 | 9 | oveq2d |  | 
						
							| 11 | 10 | raleqdv |  | 
						
							| 12 | 11 | biimpcd |  | 
						
							| 13 | 12 | adantr |  | 
						
							| 14 | 13 | adantl |  | 
						
							| 15 | 14 | impcom |  | 
						
							| 16 |  | lsw |  | 
						
							| 17 |  | 2m1e1 |  | 
						
							| 18 | 17 | a1i |  | 
						
							| 19 | 18 | eqcomd |  | 
						
							| 20 | 19 | oveq2d |  | 
						
							| 21 | 1 2 | syl |  | 
						
							| 22 |  | 2cnd |  | 
						
							| 23 |  | 1cnd |  | 
						
							| 24 | 21 22 23 | subsubd |  | 
						
							| 25 | 20 24 | eqtrd |  | 
						
							| 26 | 25 | fveq2d |  | 
						
							| 27 | 16 26 | eqtrd |  | 
						
							| 28 | 27 | adantr |  | 
						
							| 29 | 28 | adantr |  | 
						
							| 30 |  | eqeq1 |  | 
						
							| 31 | 30 | adantl |  | 
						
							| 32 | 29 31 | mpbid |  | 
						
							| 33 | 32 | preq2d |  | 
						
							| 34 | 33 | eleq1d |  | 
						
							| 35 | 34 | biimpd |  | 
						
							| 36 | 35 | ex |  | 
						
							| 37 | 36 | com13 |  | 
						
							| 38 | 37 | adantl |  | 
						
							| 39 | 38 | impcom |  | 
						
							| 40 | 39 | impcom |  | 
						
							| 41 |  | ovexd |  | 
						
							| 42 |  | fveq2 |  | 
						
							| 43 |  | fvoveq1 |  | 
						
							| 44 | 42 43 | preq12d |  | 
						
							| 45 | 44 | eleq1d |  | 
						
							| 46 | 45 | ralunsn |  | 
						
							| 47 | 41 46 | syl |  | 
						
							| 48 | 15 40 47 | mpbir2and |  | 
						
							| 49 |  | 1e2m1 |  | 
						
							| 50 | 49 | a1i |  | 
						
							| 51 | 50 | oveq2d |  | 
						
							| 52 | 51 24 | eqtrd |  | 
						
							| 53 | 52 | oveq2d |  | 
						
							| 54 | 53 | adantr |  | 
						
							| 55 |  | nn0re |  | 
						
							| 56 |  | 2re |  | 
						
							| 57 | 56 | a1i |  | 
						
							| 58 | 55 57 | subge0d |  | 
						
							| 59 | 58 | biimprd |  | 
						
							| 60 |  | nn0z |  | 
						
							| 61 |  | 2z |  | 
						
							| 62 | 61 | a1i |  | 
						
							| 63 | 60 62 | zsubcld |  | 
						
							| 64 | 59 63 | jctild |  | 
						
							| 65 | 1 64 | syl |  | 
						
							| 66 | 65 | imp |  | 
						
							| 67 |  | elnn0z |  | 
						
							| 68 | 66 67 | sylibr |  | 
						
							| 69 |  | elnn0uz |  | 
						
							| 70 | 68 69 | sylib |  | 
						
							| 71 |  | fzosplitsn |  | 
						
							| 72 | 70 71 | syl |  | 
						
							| 73 | 54 72 | eqtrd |  | 
						
							| 74 | 73 | adantr |  | 
						
							| 75 | 48 74 | raleqtrrdv |  | 
						
							| 76 | 75 | ex |  |