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CSharp · Console

/Program.cs

using System;

public class Program
{
	public static void Main()
	{
		int n = 0;
		for (int i = 0; i <= 4; i++)
		{
			for (int j = i + 1; j <= 4; j++)
			{
				for (int k = j + 1; k <= 4; k++)
				{
					n++;
					Console.WriteLine("{0}: ({1},{2},{3})", n, i, j, k);
				}
			}
		}
	}
}