import java.util.*;
import java.lang.*;
import java.io.*;
/* Name of the class has to be "Main" only if the class is public. */
class Ideone
{
public static void main (String[] args) throws java.lang.Exception
{
Scanner in = new Scanner(System.in);
int t = Integer.parseInt(in.nextLine());
int i=1;
while(i <= t){
int n = Integer.parseInt(in.nextLine());
String input = in.nextLine();
System.out.println("Test Case #"+i);
periodString(input,n);
i++;
System.out.println();
}
}
private static void periodString(String in,int len){
int[] lps = prefixTable(in);
int i=0;
int n;
int k;
for(i=0;i<len;i++){
if(lps[i] != 0) {
n = i+1; //length of string ..upto i.
int t = n-lps[i];
if(t > 0 && n % t == 0){
k = n/t;
System.out.println(n+" " +k);
}
}
}
}
private static int[] prefixTable(String pattern) {
int n = pattern.length();
int[] lps = new int[n];
int len = 0; // length of common prefix n suffix
lps[0] = 0;
int i = 1;
while (i < n) {
if (pattern.charAt(i) == pattern.charAt(len)) {
len++;
lps[i] = len;
i++;
} else {
if (len > 0) {
len = lps[len - 1];
} else {
lps[i] = 0; // len = 0
i++;
}
}
}
return lps;
}
}