| Step | Hyp | Ref | Expression | 
						
							| 1 |  | sumdmdi.1 |  | 
						
							| 2 |  | sumdmdi.2 |  | 
						
							| 3 | 1 2 | chjcli |  | 
						
							| 4 | 3 | cheli |  | 
						
							| 5 |  | spansnsh |  | 
						
							| 6 | 2 | chshii |  | 
						
							| 7 |  | shsub2 |  | 
						
							| 8 | 5 6 7 | sylancl |  | 
						
							| 9 |  | spansnid |  | 
						
							| 10 | 8 9 | sseldd |  | 
						
							| 11 | 10 | ad2antrl |  | 
						
							| 12 |  | elin |  | 
						
							| 13 |  | df-ne |  | 
						
							| 14 |  | spansna |  | 
						
							| 15 | 13 14 | sylan2br |  | 
						
							| 16 |  | oveq1 |  | 
						
							| 17 | 16 | ineq1d |  | 
						
							| 18 | 16 | ineq1d |  | 
						
							| 19 | 18 | oveq1d |  | 
						
							| 20 | 17 19 | sseq12d |  | 
						
							| 21 | 20 | rspcv |  | 
						
							| 22 | 15 21 | syl |  | 
						
							| 23 |  | spansnj |  | 
						
							| 24 |  | spansnch |  | 
						
							| 25 |  | chjcom |  | 
						
							| 26 | 24 25 | sylan2 |  | 
						
							| 27 | 23 26 | eqtrd |  | 
						
							| 28 | 2 27 | mpan |  | 
						
							| 29 | 28 | ineq1d |  | 
						
							| 30 | 28 | ineq1d |  | 
						
							| 31 | 30 | oveq1d |  | 
						
							| 32 | 29 31 | sseq12d |  | 
						
							| 33 | 32 | adantr |  | 
						
							| 34 | 22 33 | sylibrd |  | 
						
							| 35 | 34 | com12 |  | 
						
							| 36 | 35 | expdimp |  | 
						
							| 37 |  | ssid |  | 
						
							| 38 |  | sneq |  | 
						
							| 39 | 38 | fveq2d |  | 
						
							| 40 |  | spansn0 |  | 
						
							| 41 | 39 40 | eqtrdi |  | 
						
							| 42 | 41 | oveq2d |  | 
						
							| 43 | 6 | shs0i |  | 
						
							| 44 | 42 43 | eqtrdi |  | 
						
							| 45 | 44 | ineq1d |  | 
						
							| 46 |  | inss1 |  | 
						
							| 47 | 2 1 | chub2i |  | 
						
							| 48 | 37 47 | ssini |  | 
						
							| 49 | 46 48 | eqssi |  | 
						
							| 50 | 45 49 | eqtrdi |  | 
						
							| 51 | 44 | ineq1d |  | 
						
							| 52 | 51 | oveq1d |  | 
						
							| 53 | 2 1 | chincli |  | 
						
							| 54 | 53 2 | chjcomi |  | 
						
							| 55 | 2 1 | chabs1i |  | 
						
							| 56 | 54 55 | eqtri |  | 
						
							| 57 | 52 56 | eqtrdi |  | 
						
							| 58 | 50 57 | sseq12d |  | 
						
							| 59 | 37 58 | mpbiri |  | 
						
							| 60 | 36 59 | pm2.61d2 |  | 
						
							| 61 | 60 | adantrr |  | 
						
							| 62 | 1 2 | sumdmdlem |  | 
						
							| 63 | 62 | oveq1d |  | 
						
							| 64 | 63 56 | eqtrdi |  | 
						
							| 65 | 1 | chshii |  | 
						
							| 66 | 6 65 | shsub2i |  | 
						
							| 67 | 64 66 | eqsstrdi |  | 
						
							| 68 | 67 | adantl |  | 
						
							| 69 | 61 68 | sstrd |  | 
						
							| 70 | 69 | sseld |  | 
						
							| 71 | 12 70 | biimtrrid |  | 
						
							| 72 | 11 71 | mpand |  | 
						
							| 73 | 72 | exp32 |  | 
						
							| 74 | 73 | com34 |  | 
						
							| 75 |  | pm2.18 |  | 
						
							| 76 | 74 75 | syl8 |  | 
						
							| 77 | 4 76 | syl5 |  | 
						
							| 78 | 77 | pm2.43d |  | 
						
							| 79 | 78 | ssrdv |  | 
						
							| 80 | 1 2 | chsleji |  | 
						
							| 81 | 79 80 | jctil |  | 
						
							| 82 |  | eqss |  | 
						
							| 83 | 81 82 | sylibr |  |