/* MIDI Olympiad in Informatics 2007
 * Reflections reference solution
 * by Daumilas Ardickas
 */

#include <iostream>
#include <ctime>
using namespace std;
int oiler (int x){
    int d=2, o=1;
    while (d*d<=x){
        if (!(x%d)){
            x/=d;
            o*=(d-1);
            while (!(x%d)){
                o*=d;
                x/=d;
            }
        }
        ++d;
    }
    if (x>1) o*=(x-1);
    return o;
}
int main(){
    freopen("reflections.in", "r", stdin);
    freopen("reflections.out", "w", stdout);
    int a, b, i;
    while (scanf("%i%i", &a, &b)==2){
        long long x=0;
        for (i=a+1; i<=b+1; ++i) x+=(long long)oiler(i);
        cout << x << endl;
        //printf ("%f\n", (double)clock()/CLOCKS_PER_SEC);
    }
}