Part of the series

Several example codes

~2 min read • Updated Oct 1, 2025

Program Overview

This Python program uses nested loops to print a triangle of numbers.
Each row begins with a circle symbol followed by an increasing sequence of numbers starting from 1.
The number of elements in each row increases by one until the final row.


Python Code:


# Read number of rows from user
n = int(input("Enter number of rows: "))

# Generate pattern using nested loops
for i in range(1, n + 1):
    print("◯", end=" ")
    for j in range(1, i + 1):
        print(j, end=" ")
    print()

Sample Output:


Enter number of rows: 8  

◯ 1  
◯ 1 2  
◯ 1 2 3  
◯ 1 2 3 4  
◯ 1 2 3 4 5  
◯ 1 2 3 4 5 6  
◯ 1 2 3 4 5 6 7  
◯ 1 2 3 4 5 6 7 8

Step-by-Step Explanation:

- The outer loop controls the number of rows
- Each row starts with the symbol
- The inner loop prints numbers from 1 up to the current row index
- end=" " keeps output on the same line
- print()


Written & researched by Dr. Shahin Siami