推 LPH66:為什麼會花了你5分鐘啊...!? 61.62.178.179 02/11
→ LPH66:第一個看到natural就想到自然數啊... 61.62.178.179 02/11
推 darkseer:大概是想太多....218.175.187.247 02/12
This problem is from AoPS.
http://www.artofproblemsolving.com/Forum/viewtopic.php?t=26137
n, a, and b are natural numbers. Prove that:
1 1 1
--- + --- + ... + ---- isn't natural.
a a+b a+nb
By being natural, we mean that number is a positive integer.
Your English may not be as poor as mine, but it takes me 5 mins to
understand it orz...
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※ 編輯: darkseer 來自: 218.175.182.32 (02/11 22:16)