#include<fstream>
using namespace std;
ifstream cin("frac.in");
ofstream cout("frac.out");
long long n,p;
bool cmmdc(long long a,long long b){
	while(a!=b){
		if(a>b)a-=b;
		else b-=a;
	}
	if(a==1)return 1;
	return 0;
}
int main(){
	cin>>n>>p;
	long long aux=0,rs=0;
	bool t=true;
	while(t){
		aux++;
		if(cmmdc(aux,n)){
			rs++;
		}
		if(rs==p){cout<<aux;t=0;}
	}
}