#include <fstream>

using namespace std;


int main()
{unsigned long n,p,aux_n,div,div_primi[100],fr_grupa,numarator,fractii;
     int grupe,ok,indice,i;
    ifstream f("frac.in");
    f>>n>>p;
    f.close();
     aux_n=n;div=2;
     while (aux_n>1)
     {
           if (aux_n%div==0) 
             {  div_primi[++indice]=div;
                 while (aux_n%div==0) aux_n=aux_n/div;
                 }
                 div++;
                 }
                 
fractii=1;
numarator=2;
  while (numarator<n)
    {ok=1;
       for(i=1;i<=indice;i++)
         if (numarator%div_primi[i]==0) {ok=0;break;}
         if(ok==1) fractii++;
         
         }
         
grupe=p/fractii;
fr_grupa=p%fractii;

fractii=1;
numarator=2;
  while (fractii<fr_grupa)
    {ok=1;
       for(i=1;i<=indice;i++)
         if (numarator%div_primi[i]==0) {ok=0;break;}
         if(ok==1) fractii++;
         
         }
 ofstream g("frac.out");        
g<<n*grupe+numarator;
g.close();
          }