QOJ.ac

QOJ

시간 제한: 1.0 s 메모리 제한: 256 MB 총점: 100

#15749. A先生的想法

통계

A 先生向他的儿子提出了以下问题:

“考虑两个整数 $n_1$ 和 $n_2$,满足 $1 \le n_1 < n_2 \le 10^4$。利用函数 $p: \mathbb{N}^* \to \mathbb{N}^*$,$p(n) = 2^n, \forall n \in \mathbb{N}^*$(其中 $\mathbb{N}^*$ 是正整数集合),我们定义集合: $$S(n_1, n_2) = \{ p(p(n)) + 1 \mid n_1 \le n \le n_2 \}$$

我们还定义一个数对集合如下: $$T(n_1, n_2) = \{ (m_1, m_2) \mid m_1, m_2 \in S(n_1, n_2), m_1 < m_2 \}$$

考虑以下公式: $$R(n_1, n_2) = \sum_{(m_1, m_2) \in T(n_1, n_2)} \gcd(m_1, m_2)$$ 其中 $\gcd(m_1, m_2)$ 是 $m_1$ 和 $m_2$ 的最大公约数。问题要求计算出数值 $R(n_1, n_2)$。”

请解决 A 先生提出的这个问题。

输入格式

输入仅包含一行,包含两个由空格隔开的整数 $n_1$ 和 $n_2$。

输出格式

输出仅包含一行,即 $R(n_1, n_2)$ 的值。

样例

输入样例 1

1 34

输出样例 1

561

输入样例 2

15 147

输出样例 2

8778

输入样例 3

125 1000

输出样例 3

383250

Discussions

About Discussions

The discussion section is only for posting: General Discussions (problem-solving strategies, alternative approaches), and Off-topic conversations.

This is NOT for reporting issues! If you want to report bugs or errors, please use the Issues section below.

Open Discussions 0
No discussions in this category.

Issues

About Issues

If you find any issues with the problem (statement, scoring, time/memory limits, test cases, etc.), you may submit an issue here. A problem moderator will review your issue.

Guidelines:

  1. This is not a place to publish discussions, editorials, or requests to debug your code. Issues are only visible to you and problem moderators.
  2. Do not submit duplicated issues.
  3. Issues must be filed in English or Chinese only.
Active Issues 0
No issues in this category.
Closed/Resolved Issues 0
No issues in this category.