static void Main(string[] args)
{
BigInteger[] nums = new BigInteger[100000000];
Console.Write ("Número a analizar: ");
BigInteger number = BigInteger.Parse(Console.ReadLine());
collatz (number, nums);
nums = nums.Where(val => val != 0).ToArray();
foreach (BigInteger i in nums) {
Console.Write ("{0} ", i);
}
Console.WriteLine ("\n\nSTEPS = {0}", nums.Length - 1);
Console.Read ();
}