Increasing Number Triangle Starting from 0 in Java

What You’ll Learn

The increasing number triangle using i + j prints 0, 1 2, 2 3 4, … — a natural follow-up after Program 33’s i + j - 1 triangle starting from 1. This tutorial covers the i + j formula, nested loops, a live preview, worked Java examples, edge cases, and complexity.

📝 Problem & Approach

Given max = 5, print a zero-based left-shifted increasing triangle: for each row i, print j = 0..i values of i + j separated by spaces.

// max = 5 (i runs 0..5)
// 0
// 1 2
// 2 3 4
// 3 4 5 6
// 4 5 6 7 8
// 5 6 7 8 9 10

Inputs & Outputs

Minimal workflow

for i from 0 to max:
    for j from 0 to i:
        print (i + j) + space
    print newline

Approach comparison

🔮 Live Preview

Choose a max i value between 2 and 9 and draw the increasing triangle in the browser.

Press "Draw pattern".

Examples Gallery

Three complete Java programs — fixed max, user input, and a smaller trace demo. Click View Output to reveal sample console results.

public class IncreasingFrom0 {
    public static void main(String[] args) {
        for (int i = 0; i <= 5; i++) {
            for (int j = 0; j <= i; j++)
                System.out.print((i + j) + " ");
            System.out.println();
        }
    }
}

0
1 2
2 3 4
3 4 5 6
4 5 6 7 8
5 6 7 8 9 10

import java.util.Scanner;

public class IncreasingFrom0Input {
    public static void main(String[] args) {
        Scanner sc = new Scanner(System.in);
        System.out.print("Enter max i: ");
        int max = sc.nextInt();
        if (max < 0) return;

        for (int i = 0; i <= max; i++) {
            for (int j = 0; j <= i; j++)
                System.out.print((i + j) + " ");
            System.out.println();
        }
        sc.close();
    }
}

Enter max i: 2
0
1 2
2 3 4

public class IncreasingFrom0Small {
    public static void main(String[] args) {
        int max = 2;

        for (int i = 0; i <= max; i++) {
            for (int j = 0; j <= i; j++)
                System.out.print((i + j) + " ");
            System.out.println();
        }
    }
}

0
1 2
2 3 4

🔎 Worked Walkthrough — max = 5

Trace each outer-loop value of i, inner-loop range, values printed, and full row output.

Prints per row = i + 1 — total prints = (max+1)(max+2)/2 when i runs 0..max.

🎯 Practice Problems

Try these variations to lock in the pattern.

Notes

⏱️ Time and Space Complexity

💡 Best Practices