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[组合] 2013个数染色问题

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realnumber Posted 2016-4-6 13:51 |Read mode
浙江 斜霜(51#####39) 17:24:41
可否将所有正整数用2013种颜色染色,使得对任意正整数n,下面2013个数:n,2n,3n,…,2013n的颜色两两不同?

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 Author| realnumber Posted 2016-4-6 15:02
回复 2# 游客
继续,还是不明白。

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abababa Posted 2016-4-6 21:33
能不能用模?把2013种颜色编号为$0$到$2012$,对任意正整数$k$,将它染成第$k \mod 2013$号颜色。这样对任意的$n$,数$n,2n,3n,\cdots,2013n$的颜色编号就都不同了。

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abababa Posted 2016-4-6 21:41
回复 4# abababa

哦,这个不对,当$n=2013$时就是反例。

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