303932: CF757E. Bash Plays with Functions

Memory Limit:256 MB Time Limit:3 S
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Description

Bash Plays with Functions

题意翻译

定义函数 $f_r(n)$: - 在 $r=0$ 时,为满足 $p\cdot q=n$ 且 $\gcd(p,q)=1$ 的有序对 $(p,q)$ 个数; - 在 $r\ge1$ 时,$\displaystyle f_r(n)=\sum_{u\cdot v=n}\frac{f_{r-1}(u)+f_{r-1}(v)}{2}$。 一共 $q$ 组询问,每组询问给出 $r,n$,求 $f_r(n)$ 模 $10^9+7$ 的结果。 数据范围:$q\le10^6$,$0\le r\le10^6$,$1\le n\le10^6$。

题目描述

Bash got tired on his journey to become the greatest Pokemon master. So he decides to take a break and play with functions. Bash defines a function $ f_{0}(n) $ , which denotes the number of ways of factoring $ n $ into two factors $ p $ and $ q $ such that $ gcd(p,q)=1 $ . In other words, $ f_{0}(n) $ is the number of ordered pairs of positive integers $ (p,q) $ such that $ p·q=n $ and $ gcd(p,q)=1 $ . But Bash felt that it was too easy to calculate this function. So he defined a series of functions, where $ f_{r+1} $ is defined as: ![](https://cdn.luogu.com.cn/upload/vjudge_pic/CF757E/ba3f455e23406140b1481185211a534c2e0f9d49.png)Where $ (u,v) $ is any ordered pair of positive integers, they need not to be co-prime. Now Bash wants to know the value of $ f_{r}(n) $ for different $ r $ and $ n $ . Since the value could be huge, he would like to know the value modulo $ 10^{9}+7 $ . Help him!

输入输出格式

输入格式


The first line contains an integer $ q $ ( $ 1<=q<=10^{6} $ ) — the number of values Bash wants to know. Each of the next $ q $ lines contain two integers $ r $ and $ n $ ( $ 0<=r<=10^{6} $ , $ 1<=n<=10^{6} $ ), which denote Bash wants to know the value $ f_{r}(n) $ .

输出格式


Print $ q $ integers. For each pair of $ r $ and $ n $ given, print $ f_{r}(n) $ modulo $ 10^{9}+7 $ on a separate line.

输入输出样例

输入样例 #1

5
0 30
1 25
3 65
2 5
4 48

输出样例 #1

8
5
25
4
630

Input

题意翻译

定义函数 $f_r(n)$: - 在 $r=0$ 时,为满足 $p\cdot q=n$ 且 $\gcd(p,q)=1$ 的有序对 $(p,q)$ 个数; - 在 $r\ge1$ 时,$\displaystyle f_r(n)=\sum_{u\cdot v=n}\frac{f_{r-1}(u)+f_{r-1}(v)}{2}$。 一共 $q$ 组询问,每组询问给出 $r,n$,求 $f_r(n)$ 模 $10^9+7$ 的结果。 数据范围:$q\le10^6$,$0\le r\le10^6$,$1\le n\le10^6$。

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