#include <stdio.h>
#include <string.h>
#include <algorithm>
#include <iostream>
#include <math.h>
using namespace std;
typedef long long LL;
const int N =3000005;
LL euler[N];
//LL sum[N];
void getEuler()
{
    memset(euler,0,sizeof(euler));
    euler[1] = 1;
    for(int i = 2; i <= N; i++){
        if(!euler[i])
            for(int j = i; j <= N; j+= i)
            {
                if(!euler[j])
                    euler[j] = j;
                euler[j] = euler[j]/i*(i-1);
            }
        //sum[i]=sum[i-1]+(LL)euler[i];
    }
}

int main()
{
    getEuler();
    int a,b;
    while(~scanf("%d%d",&a,&b)){
        LL sum = 0;
        for(int i=a;i<=b;i++){
            sum+=euler[i];
        }
        printf("%lld\n",sum);
    }
    return 0;
}