#include<stdio.h>
int k;
int a[14];

int is_ok(int n)
{
    int rem=2*k;
    int kill=(n%rem?n%rem:rem);
    while(kill>k)
    {
        rem--;
        if(rem==k)return 1;
        kill=(kill+n-1)%rem;
        kill=kill?kill:rem;
    }
    return 0;
}

void main()
{
    int i,j;
    for(i=0;i<14;a[i++]=0);
    while(scanf("%d",&k)&&k)
    {
        if(a[k])goto inx;
        for(j=k;;j+=2*k)
        {
            for(i=j+1;i<=j+k;i++)
            {
                if(is_ok(i)){a[k]=i;goto inx;}
            }
        }
inx:
        printf("%d\n",a[k]);
    }
}