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Problem 207


Problem 207


Integer partition equations

For some positive integers k, there exists an integer partition of the form   4t = 2t + k,
where 4t, 2t, and k are all positive integers and t is a real number.

The first two such partitions are 41 = 21 + 2 and 41.5849625… = 21.5849625… + 6.

Partitions where t is also an integer are called perfect.
For any m ≥ 1 let P(m) be the proportion of such partitions that are perfect with k ≤ m.
Thus P(6) = 1/2.

In the following table are listed some values of P(m)

P(5) = 1/1
P(10) = 1/2
P(15) = 2/3
P(20) = 1/2
P(25) = 1/2
P(30) = 2/5

P(180) = 1/4
P(185) = 3/13

Find the smallest m for which P(m) < 1/12345


整数分拆等式

对于某些正整数k,存在形如4t = 2t + k的整数分拆,
其中4t,2t和k均为正整数,而t为实数。

前两个这样的分拆分别是41 = 21 + 2和41.5849625… = 21.5849625… + 6。

如果t也是整数,这样的分拆称为完美的
对于任意m ≥ 1,记P(m)是所有k ≤ m的分拆中完美分拆的比例。
因此P(6) = 1/2。

下面的表格列出了P(m)的部分取值:

P(5) = 1/1
P(10) = 1/2
P(15) = 2/3
P(20) = 1/2
P(25) = 1/2
P(30) = 2/5

P(180) = 1/4
P(185) = 3/13

求出使得P(m) < 1/12345的最小m值。