C2023034 2024-02-26 9:47:40 2024-02-26 9:48:18
#include<bits/stdc++.h> using namespace std;
int main() { int n; cin>>n; long long s=0; for(int x=1;x<=n;x++)
{ s=s+x*(x+1); } cout<<s; return 0;
}
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