#include<stdio.h>
   int main()
{
  long i=0, n, p, s=0, t, k;

     freopen("frac.in", "r", stdin);
     freopen("frac.out", "w", stdout);

     scanf("%ld%ld", &n, &p);

 while(s<p)
  {  i++;
    t=i; k=n;
     while(t!=0 && k!=0)
     {
       if(t>k)
        t=t%k;
       else
        k=k-t;
     }
      if(k+t==1)
       s++;

  }

 printf("%ld", i);

return 0;

}