 mso-text-raise: -2.0pt">i+1</span></sub><span style="position: relative; top: 2pt; mso-text-raise: -2.0pt">=</span></font></span><span lang="EN-US" style="font-family: 宋体; position: relative; top: 2pt; mso-text-raise: -2.0pt">+</span><span style="font-family: 宋体; position: relative; top: 2pt; mso-text-raise: -2.0pt">&infin;</span><span style="font-family: 宋体; mso-ascii-font-family: 'Times New Roman'; mso-hansi-font-family: 'Times New Roman'">，那么当他制造第</span><span lang="EN-US"><fo