func_code_string: #include <bits/stdc++.h>   using namespace std;   int spf[5000002];   int f[5000002];   void init() {     spf[0] = spf[1] = 1;     for (int i = 2; i < 5000002; ++i) {       if (spf[i] == 0) {         spf[i] = i;         long long int start = 1LL * i * i;         for (long long int j = start; j < 5000002; j += i) {           if (spf[j] == 0) spf[j] = i;         }       }     }     f[0] = f[1] = 0;     for (int i = 2; i < 5000002; ++i) {       int x = spf[i];       int y = i / x;       long long int val = 1LL * y * x * (x - 1) / 2 + f[y];       f[i] = val % 1000000007;     }   }   int main(void) {     ios::sync_with_stdio(false);     cin.tie(NULL);     init();     int t, l, r;     cin >> t >> l >> r;     long long int ans = 0, mul = 1;     for (int i = 0; i <= r - l; ++i) {       ans = ans + (mul * f[i + l]) % 1000000007;       mul = (mul * t) % 1000000007;     }     cout << ans % 1000000007 <<   n ;   }   