#include<bits/stdc++.h> using namespace std; int main(){ int n; cin >> n; while(n--) { int k; cin >> k; long long a[10010] = {}; a[1] = 2; for(int i = 2; i <= k; i++) { a[i] = a[i - 1] + i; } cout << a[k] << endl; } return 0; }

#include<bits/stdc++.h> using namespace std; int main() { int t,n; cin>>t; while(t--) { cin>>n; cout<<1 + n * (n + 1) / 2 << endl; } return 0; }