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A13819. Lonely Numbers

编程题 普及/提高-

题目描述

In number world, two different numbers are friends if they have a lot in common, but also each one has unique perks.

More precisely, two different numbers $a$ and $b$ are friends if $gcd(a,b)$ , $\frac{a}{gcd(a,b)}$ , $\frac{b}{gcd(a,b)}$ can form sides of a triangle.

Three numbers $a$ , $b$ and $c$ can form sides of a triangle if $a + b > c$ , $b + c > a$ and $c + a > b$ .

In a group of numbers, a number is lonely if it doesn't have any friends in that group.

Given a group of numbers containing all numbers from $1, 2, 3, ..., n$ , how many numbers in that group are lonely?

输入格式

The first line contains a single integer $t$ $(1 \leq t \leq 10^6)$ - number of test cases.

On next line there are $t$ numbers, $n_i$ $(1 \leq n_i \leq 10^6)$ - meaning that in case $i$ you should solve for numbers $1, 2, 3, ..., n_i$ .

输出格式

For each test case, print the answer on separate lines: number of lonely numbers in group $1, 2, 3, ..., n_i$ .

输入输出样例

输入 #1
3
1 5 10
输出 #1
1
3
3

说明/提示

For first test case, $1$ is the only number and therefore lonely.

For second test case where $n=5$ , numbers $1$ , $3$ and $5$ are lonely.

For third test case where $n=10$ , numbers $1$ , $5$ and $7$ are lonely.
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