| Step | Hyp | Ref | Expression | 
						
							| 1 |  | esumfsup.1 |  | 
						
							| 2 |  | icossicc |  | 
						
							| 3 |  | fss |  | 
						
							| 4 | 2 3 | mpan2 |  | 
						
							| 5 | 1 | esumfsup |  | 
						
							| 6 | 4 5 | syl |  | 
						
							| 7 |  | 1zzd |  | 
						
							| 8 |  | elnnuz |  | 
						
							| 9 |  | ffvelcdm |  | 
						
							| 10 | 8 9 | sylan2br |  | 
						
							| 11 |  | ge0addcl |  | 
						
							| 12 | 11 | adantl |  | 
						
							| 13 |  | rge0ssre |  | 
						
							| 14 |  | simprl |  | 
						
							| 15 | 13 14 | sselid |  | 
						
							| 16 |  | simprr |  | 
						
							| 17 | 13 16 | sselid |  | 
						
							| 18 |  | rexadd |  | 
						
							| 19 | 18 | eqcomd |  | 
						
							| 20 | 15 17 19 | syl2anc |  | 
						
							| 21 | 7 10 12 20 | seqfeq3 |  | 
						
							| 22 | 21 | rneqd |  | 
						
							| 23 | 22 | supeq1d |  | 
						
							| 24 | 6 23 | eqtr4d |  |