#include<iostream>
#include<fstream>
using namespace std;
int n,p,i,j,v[1000],ok;
ifstream f("frac.in");
ofstream g("frac.out");
int cmmdc(int x,int y,int ok)
	{while(x!=y)
	if(x>y)
		x=x-y;
	else y=y-x;
	if(x!=1&&y!=1)
		ok=0;;
	return ok;}
int main()
{f>>n>>p;
i=0;
j=0;
while(i<=p)
 	{j++;
 	if(cmmdc(j,n,1)==1)
 		{i++;
 		v[i]=j;
 		}
 	}
cout<<v[p];
f.close();
g.close();
return 0;
}