#include<bits/stdc++.h>

 using namespace std;

 #define pb(x) push_back(x)

 #define ll long long

 #define mk(x, y) make_pair(x, y)

 #define lson l, m, rt<<1

 #define mem(a) memset(a, 0, sizeof(a))

 #define rson m+1, r, rt<<1|1

 #define mem1(a) memset(a, -1, sizeof(a))

 #define mem2(a) memset(a, 0x3f, sizeof(a))

 #define rep(i, a, n) for(int i = a; i<n; i++)

 #define ull unsigned long long

 typedef pair<int, int> pll;

 const double PI = acos(-1.0);

 const double eps = 1e-;

 const int mod = 1e9+;

 const int inf = ;

 const int dir[][] = { {-, }, {, }, {, -}, {, } };

 const int maxn = 3e6+;;

 int f[maxn];

 int main()

 {

     int t, n, m, cnt;

     for(int i = ; i<=maxn; i++) {

         f[i] = i;

     }

     for(int i = ; i<maxn; i++) {

         if(f[i] == i) {             //如果f[i] == i， 说明这个数是素数

             for(int j = i; j<maxn; j+=i) {

                 f[j] = f[j]/i*(i-);            //f[j]*(1-1/i)

             }

         }

     }

     while(~scanf("%d%d", &n, &m)) {

         ll sum = ;

         for(int i = n; i<=m; i++) {

             sum += f[i];

         }

         cout<<sum<<endl;

     }

 }