#include <stdio.h>

#include <string.h>

#include <algorithm>

#include <iostream>

#include <math.h>

using namespace std;

typedef long long LL;

const int N =;

LL euler[N];

//LL sum[N];

void getEuler()

{

    memset(euler,,sizeof(euler));

    euler[] = ;

    for(int i = ; 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-);

            }

        //sum[i]=sum[i-1]+(LL)euler[i];

    }

}

int main()

{

    getEuler();

    int a,b;

    while(~scanf("%d%d",&a,&b)){

        LL sum = ;

        for(int i=a;i<=b;i++){

            sum+=euler[i];

        }

        printf("%lld\n",sum);

    }

    return ;

}