#include<stdio.h>
#include<stdlib.h>
#include<math.h>
struct node{
    int no;
    struct node *next;
};
int prime[5000],nprime;
int main(){
    int i,j;
    int sq;
    int check;
    int n;
    int cut,count;
    struct node *member,*ptr,*current;
    prime[0]=2;
    nprime=1;
    for(i=3;nprime<=3502;i+=2){
        check=1;
        sq=sqrt(i);
        for(j=3;j<=sq;j+=2){
            if(i%j==0){
                check=0;
                break;
            }
        }
        if(check==1){
            prime[nprime++]=i;
        }
    }
    while(1){
        scanf("%d",&n);
        if(n==0)break;
        if(n==1){printf("1\n");continue;}
        member=(struct node*)malloc(sizeof(struct node));
        member->no=1;
        member->next=NULL;
        current=member;
        for(i=2;i<=n;i++){
            ptr=(struct node*)malloc(sizeof(struct node));
            current->next=ptr;
            ptr->no=i;
            ptr->next=NULL;
            current=ptr;
        }
        current->next=member;
        /*current=member;*/
        count=0;
        while(n>1){
            cut=prime[count++];
            /*if(count==1)cut--;*/
            cut = (cut-1) % n + 1;
            /*printf("(%d)",cut);*/
            while(cut--){
                ptr=current;
                current=current->next;
            }
            /*printf("[%d]\n",current->no);*/
            ptr->next=current->next;
            /*free(current);*/
            current=ptr;
            n--;
        }
        printf("%d\n",ptr->no);
    }
    getchar();
    return 0;
}