brz的函数

brz的函数

/*
  Author : lifehappy
*/
#include <bits/stdc++.h>

using namespace std;

const int N = 5e4 + 10;

int prime[N], mu[N], ans[N], cnt, n;

bool st[N];

void init() {
    mu[1] = 1;
    for(int i = 2; i < N; i++) {
        if(!st[i]) {
            prime[++cnt] = i;
            mu[i] = -1;
        }
        for(int j = 1; j <= cnt && 1ll * i * prime[j] < N; j++) {
            st[i * prime[j]] = 1;
            if(i % prime[j] == 0) {
                break;
            }
            mu[i * prime[j]] = -mu[i];
        }
    }
    for(int d = 1; d < N; d++) {
        int res = 0;
        for(int l = d; l < N; l += d) {
            int r = l + d - 1;
            r = min(r, N - 2);
            res += mu[l];
            ans[l] += mu[d] * res * res;
            ans[r + 1] -= mu[d] * res * res;
        }
    }
    for(int i = 1; i < N; i++) {
        ans[i] += ans[i - 1];
    }
}

int main() {
    // freopen("in.txt", "r", stdin);
    // freopen("out.txt", "w", stdout);
    // ios::sync_with_stdio(false), cin.tie(0), cout.tie(0);
    init();
    int T;
    scanf("%d", &T);
    while(T--) {
        scanf("%d", &n);
        printf("%d\n", ans[n]);
    }
    return 0;
}