using System;
using System.Collections;
// Generates a sequence of 4-digit numbers in which every number
// is the square of the middle digits of its predcessor
class NumberSequence {
static void Main(string[] arg) {
int num = 1234;
if (arg.Length > 0) num = Convert.ToInt32(arg[0]);
ArrayList list = new ArrayList();
while (!list.Contains(num)) {
list.Add(num);
int x = num / 10 % 100;
num = x * x;
}
foreach (int x in list) Console.Write(x + " ");
}
}
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