#include<cmath>
#include<queue>
#include<deque>
#include<stack>
#include<cstdio>
#include<cstring>
#include<cstdlib>
#include<iostream>
#include<algorithm>
using namespace std;
#define Max(a,b) a>b?a:b
#define Min(a,b) a>b?b:a
#define mem(a,b) memset(a,b,sizeof(a))
int dir[4][2]= {{0,-1},{-1,0},{0,1},{1,0}};
const double eps = 1e-6;
const double Pi = acos(-1.0);
#define maxn 1000005
int prime[maxn];
bool flag[maxn];
int cc=0;
void prim()
{
for(int i=2; i<=maxn; i++)
{
if(!flag[i])
{
prime[cc++]=i;
for(int j=2; j*i<maxn; j++)
{
flag[j*i]=1;
}
}
}
}
//容斥原理
long long int dfs(int nn,long long int mm)
{
long long int sum=0;
for(int i=nn; i<cc&&(long long int)prime[i]*prime[i]<=mm; i++)
{
sum+=mm/prime[i]/prime[i]-dfs(i+1,mm/prime[i]/prime[i]);
}
return sum;
}
int main()
{
//freopen("1.txt","r",stdin);
//freopen("2.txt","w",stdout);
prim();
long long int n,m;
while(~scanf("%lld%lld",&n,&m))
{
printf("%lld\n",(m-dfs(0,m))-(n-dfs(0,n))+1);
}
return 0;
}