#include<stdio.h>
#include<iostream>
#include<string.h>
#include<string>
#include<ctype.h>
#include<math.h>
#include<set>
#include<map>
#include<vector>
#include<queue>
#include<bitset>
#include<algorithm>
#include<time.h>
using namespace std;
void fre() { freopen("c://test//input.in", "r", stdin); freopen("c://test//output.out", "w", stdout); }
#define MS(x,y) memset(x,y,sizeof(x))
#define MC(x,y) memcpy(x,y,sizeof(x))
#define MP(x,y) make_pair(x,y)
#define ls o<<1
#define rs o<<1|1
typedef long long LL;
typedef unsigned long long UL;
typedef unsigned int UI;
template <class T1, class T2>inline void gmax(T1 &a, T2 b) { if (b>a)a = b; }
template <class T1, class T2>inline void gmin(T1 &a, T2 b) { if (b<a)a = b; }
const int N = 1e6+10, M = 0, Z = 1e9 + 7, ms63 = 0x3f3f3f3f;
template <class T1, class T2>inline void gadd(T1 &a, T2 b) { a+=b; a%=Z; }

int casenum, casei;

int pr[33000],tot;
bool vis[34000];
int n,d;
void init()
{
    tot = 0;
    for(int i = 2; i <= 33000; ++i)
    {
        if(!vis[i]) pr[tot++] = i;
        for(int j = i*i; j <= 33000; j+=i)
            vis[j] = 1;
    }
}
void solve()
{
    scanf("%d%d",&n,&d);
    int top = (n-1)/d;
    gmin(top,d);
    for(int i = 0; pr[i] < top && pr[i]*pr[i] <= d; ++i)
    {
        if(d%pr[i] == 0)
        {
            gmin(top,pr[i]);
            break;
        }
    }
    int ans = upper_bound(pr,pr+tot,top) - pr;
    printf("%d\n",ans);
}
int main()
{
    init();
    int T;
    scanf("%d",&T);
    while(T--)solve();
}