#include <cstdio>

const int MAX_E = 1000000;
int ciur[1+MAX_E];
int vect[8][1+MAX_E];
int top[8];

int bins(int st, int dr, int k, int n) {
  while(dr - st > 1) {
    int mid = (st + dr) / 2;
    if(vect[k][mid] <= n)
      st = mid;
    else
      dr = mid;
  }
  return vect[k][st];
}

int main() {
  int t, n, k;
  for(int i = 0; i <= 7; ++i)
    top[i]++;
  for(int d = 2; d <= MAX_E; ++d) {
    if(ciur[d] == 0) {
      for(int i = d; i <= MAX_E; i = i + d)
        ciur[i]++;
    }
    if(ciur[d] <= 7)
      vect[ciur[d]][top[ciur[d]]++] = d;
  }
  FILE *fin = fopen("divprim.in", "r");
  FILE *fout = fopen("divprim.out", "w");
  fscanf(fin, "%d", &t);
  for(int i = 0; i < t; ++i) {
    fscanf(fin, "%d%d", &n, &k);
    fprintf(fout, "%d\n", bins(0, top[k], k, n));
  }
  fclose(fin);
  fclose(fout);
  return 0;
}