#include <stdio.h>
int i,n,p,f;
FILE *in,*out;

int cmmdc(int a, int b);

int main(void)
{
    in=fopen("frac.in","rt");
    out=fopen("frac.out","wt");
    fscanf(in,"%d %d", &n, &p);
    for(i=1;;i++)
    {
        if(cmmdc(i,n)>1)
            continue;
        if(++f==p)
            break;
    }
    fprintf(out,"%d",i);
    fclose(in);
    fclose(out);
    return 0;
}

int cmmdc(int a, int b)
{
    int r=a%b;
    while(r)
    {
        a=b;
        b=r;
        r=a%b;
    }
    return b;
}