Why does the first row print 0?

Because the loops start at i=0 and j=0, so i + j = 0.

How do numbers increase within each row?

j increases from 0 to i, so i + j increases by 1 each step.

What is the time complexity?

O(n^2) for n rows because the total printed values are 1+2+...+(n+1).

Increasing Number Triangle Starting from 0 in C#

Beginner

⏱️ 6 min read

📚 Updated: Aug 2025

🎯 2 Code Examples

Nested Loops

Increasing number triangle output starting from 0 in C# programming

What You’ll Learn

How to generate each value as i + j while printing a triangle from i = 0 to 5.

⭐ Pattern Output

For rows = 6 (i from 0 to 5), the pattern looks like this:

Output

0\n1 2\n2 3 4\n3 4 5 6\n4 5 6 7 8\n5 6 7 8 9 10

Complete C# Program

This follows the reference program: loop i from 0 to 5 and print (i + j) for j = 0..i.

using System;

namespace MyApp
{
    class Program
    {
        static void Main(string[] args)
        {
            int i, j;

            for (i = 0; i <= 5; i++)
            {
                for (j = 0; j <= i; j++)
                    Console.Write((i + j) + " ");
                Console.WriteLine();
            }
        }
    }
}

Variation — User Input max row

Let the user choose the maximum row value (the last i):

using System;

namespace MyApp
{
    class Program
    {
        static void Main(string[] args)
        {
            Console.Write("Enter max i: ");
            int max = Convert.ToInt32(Console.ReadLine());
            if (max < 0) return;

            for (int i = 0; i <= max; i++)
            {
                for (int j = 0; j <= i; j++)
                    Console.Write((i + j) + " ");
                Console.WriteLine();
            }
        }
    }
}