<div><span style="font-family: 新細明體, serif;"><font size="4">▲</font></span><span style="font-family: 新細明體, serif; font-size: 13.6px;">&nbsp; &nbsp; &nbsp;</span><font size="4" style="font-family: &quot;Open Sans&quot;, Helvetica, Arial, sans-serif;"><b><a href="https://kknews.cc/education/kxbzej8.html" title="競賽輔導：組合恆等式的組合證明" target="" style="font-family: &quot;Open Sans&quot;, Helvetica, Arial, sans-serif;">競賽輔導：組合恆等式的組合證明</a></b></font><br></div><div><font face="Open Sans, Helvetica, Arial, sans-serif"><span style="font-size: 14px;"><br></span></font></div><div><img src="http://163.26.206.177/system/uploads/f2ea9458afb0783c3b3df322ad6547e48f3aef60.png" width="500"><br></div><div><br></div><div><br></div><div><br></div><div><br></div><div><a href="https://zh.wikipedia.org/zh-tw/%E8%8C%83%E5%BE%B7%E8%92%99%E6%81%92%E7%AD%89%E5%BC%8F" title="維基百科：范得蒙恆等式" target="" style="font-size: 13.6px;">維基百科：范得蒙恆等式</a></div>