Re: [代數] 2014emtc培訓題
※ 引述《syui (流冰～)》之銘言：
: How many numbers from 1，2，3，…，2014 have a cubic number other than 1 as a
: factor ?
: 答案:336
: 麻煩大家一下
: 謝謝
A: 8 or 27 or 125 or 343 or 1331 的倍數
以下計算
f(x) = floor(2014/x)
f(8) + f(27) + f(125) + f(343) + f(1331) - f(216) - f(1000)
= 251 + 74 + 16 + 5 + 1 - 9 - 2 = 336
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