HMMT 二月 2007 · 冲刺赛 · 第 5 题
HMMT February 2007 — Guts Round — Problem 5
题目详情
- [ 6 ] Compute the largest positive integer such that is an integer. n 2007
解析
- [ 6 ] Compute the largest positive integer such that is an integer. n 2007 2 Answer: 9 . Note that 2007 = 3 · 223. Using the fact that the number of times a prime p divides n ! is given by ⌊ ⌋ ⌊ ⌋ ⌊ ⌋ n n n
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- · · · , 2 3 p p p it follows that the answer is 9.
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