In fact ,you can say any nuber N，隻要您能說出道理.比如

來源: 於 2010-09-08 08:25:37 [博客] [舊帖] [給我悄悄話] 本文已被閱讀：次

令 f(1) = 1/2; f(2) = 1/4; f(3) = 1/4; f(4) = N,確定唯一的三次函數:
f(x) = a*x^3 + b*x^2 + c*x + d.