Python Program to Print Triangle Pattern

This blog post shows how to write a Python Program to Print Triangle Pattern of Numbers, stars, and Alphabets (characters) using for loop, while loop, and functions with an example.

Python Program to Print Triangle Star Pattern

This program accepts the user input rows and uses the nested for loop to print the triangle pattern of stars. The first Python for loop iterates from 0 to rows, and the nested loop starts at 0 and traverses up to i + 1 to print stars.

rows = int(input("Enter Rows = "))

for i in range(rows):
    for j in range(i + 1):
        print('*', end = ' ')
    print()
Program to Print Triangle Pattern using for loop

In this Python program, we use the Python while loop to print the Triangle pattern of stars.

rows = int(input("Enter Rows = "))
i = 0
while i < rows:
    j = 0
    while j <= i:
        print('*', end = ' ')
        j += 1
    print()
    i += 1
Enter Rows = 6
* 
* * 
* * * 
* * * * 
* * * * * 
* * * * * *

In this program, we have created a function that accepts the rows, and the user entered symbol (instead of a star) as a parameter and prints the Triangle pattern. For more, visit the Python star pattern programs.

def patTri(rows,  ch):
    for i in range(rows):
        for j in range(i + 1):
            print('%c' % ch, end=' ')
        print()

rows = int(input("Enter Rows = "))
ch = input("Enter Character = ")
patTri(rows,  ch)
Enter Rows = 7
Enter Character = $
$ 
$ $ 
$ $ $ 
$ $ $ $ 
$ $ $ $ $ 
$ $ $ $ $ $ 
$ $ $ $ $ $ $

Downward Triangle Star Pattern

For more information, refer to the Python Downward Triangle Star Pattern.

r = int(input("Enter Rows = "))

for i in range(r, 0, -1):
    for j in range(i):
        print('*', end = ' ')
    print()

Output

Enter Rows = 7

* * * * * * * 
* * * * * * 
* * * * * 
* * * * 
* * * 
* * 
*

Python Program to Print Left Pascal Triangle of Stars Pattern

For more information, check out the Python Left Pascal Triangle of Stars Pattern.

def loopLogic(i, r):
    for l in range(i, r):
        print(end='  ')
    for m in range(1, i + 1):
        print('*', end=' ')
    print()

r = int(input("Enter Rows = "))

for i in range(1, r + 1):
    loopLogic(i, r)

for i in range(r - 1, 0, -1):
    loopLogic(i, r)

Output

Enter Rows = 5
        * 
      * * 
    * * * 
  * * * * 
* * * * * 
  * * * * 
    * * * 
      * * 
        *

Hollow Left Pascals Triangle of Stars

For more information, check out the Python Hollow Left Pascals Triangle of Stars.

r = int(input("Enter Rows = "))

for i in range(1, r + 1):
    for j in range(r, i, -1):
        print(end = ' ')
    for k in range(1, i + 1):
        if k == 1 or k == i:
            print('*', end = '')
        else:
            print(end = ' ')      
    print()

for i in range(1, r + 1):
    for j in range(1, i + 1):
        print(end = ' ')
    for k in range(r - 1, i - 1, -1):
        if k == r - 1 or k == i:
            print('*', end = '')
        else:
            print(end = ' ')
    print()

Output

Enter Rows = 6
     *
    **
   * *
  *  *
 *   *
*    *
 *   *
  *  *
   * *
    **
     *

Right Pascals Triangle of Stars

For more information, refer to the Python Right Pascals Triangle of Stars.

def loopLogic(i, r):
    for j in range(i):
        print('*', end=' ')
    print()

r = int(input("Enter Rows = "))

for i in range(0, r):
    loopLogic(i, r)
for i in range(r, -1, -1):
    loopLogic(i, r)

Output

Enter Rows = 5

* 
* * 
* * * 
* * * * 
* * * * * 
* * * * 
* * * 
* * 
*

Hollow Right Pascals Triangle of Stars

For more information, check out the Python Hollow Right Pascals Triangle of Stars.

r = int(input("Enter Rows = "))

for i in range(1, r + 1):
    for j in range(1, i + 1):
        if j == 1 or j == i:
            print('*', end = '')
        else:
            print(end = ' ')      
    print()

for i in range(1, r + 1):
    for j in range(r - 1, i - 1, -1):
        if j == r - 1 or j == i or i == r:
            print('*', end = '')
        else:
            print(end = ' ')
    for k in range(1, i):
        print(end = ' ')
    print()

Output

Enter Rows = 6
*
**
* *
*  *
*   *
*    *
*   *
*  * 
* *  
**   
*

Python Program to Print Triangle Numbers Pattern

This section covers the different types of triangle patterns filled with numbers. For more information, see the Python Triangle Numbers Pattern.

r = int(input("Enter Rows = "))

for i in range(1, r + 1):
    for j in range(r, i, -1):
        print(end = ' ')
    for k in range(1, i + 1):
        print(k, end = ' ')
    print()

Output

Enter Rows = 5
    1 
   1 2 
  1 2 3 
 1 2 3 4 
1 2 3 4 5

Triangle of Numbers in Reverse Pattern

For more information, see the Python Triangle of Numbers in Reverse Pattern.

r = int(input("Enter Rows = "))

for i in range(r, 0, -1):
    for j in range(1, i):
        print(end = ' ')
    for k in range(i, r + 1):
        print(k, end = ' ')
    print()

Output

Enter Rows = 7
      7 
     6 7 
    5 6 7 
   4 5 6 7 
  3 4 5 6 7 
 2 3 4 5 6 7 
1 2 3 4 5 6 7

Downward Triangle of Mirrored Numbers Pattern

For more information, check out the Python Downward Triangle of Mirrored Numbers Pattern.

r = int(input("Enter Rows = "))

for i in range(1, r + 1):
    for j in range(i, r + 1):
        print(j, end = ' ')
    for k in range(r - 1, i - 1, -1):
        print(k, end = ' ')
    print()

Output

Enter Rows = 9

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

Program to Print Floyd’s Triangle

For more information, refer to the Python Floyd’s Triangle.

r = int(input("Enter Rows = "))
n = 1

for i in range(1, r + 1):
    for j in range(1, i + 1):
        print(n, end = '  ')
        n = n + 1
    print()

Output

Enter Rows = 6
1  
2  3  
4  5  6  
7  8  9  10  
11  12  13  14  15  
16  17  18  19  20  21

Inverted Triangle Numbers Pattern

For more information, see the Python Inverted Triangle Numbers Pattern.

r = int(input("Enter Rows = "))

for i in range(1, r + 1):
    for j in range(1, i):
        print(end = ' ')
    for k in range(1, r - i + 2):
        print(k, end = ' ')
    print()

Output

Enter Rows = 9

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

Triangle of Mirrored Numbers Pattern

For more information, check out the Python Triangle of Mirrored Numbers Pattern.

r = int(input("Enter Rows = "))

for i in range(1, r + 1):
    for j in range(r, i, -1):
        print(end = ' ')
    for k in range(1, i + 1):
        print(k, end = '')
    for l in range(i - 1, 0, -1):
        print(l, end = '')
    print()

Output

Enter Rows = 8
       1
      121
     12321
    1234321
   123454321
  12345654321
 1234567654321
123456787654321

Left Pascal Triangle of Numbers

For more information, visit the Python Left Pascal Triangle of Numbers.

def loopLogic(i, r):
    for j in range(i, r):
        print(end='  ')
    for k in range(1, i + 1):
        print(k, end=' ')
    print()

r = int(input("Enter Rows = "))

for i in range(1, r + 1):
    loopLogic(i, r)

for i in range(r - 1, 0, -1):
    loopLogic(i, r)

Output

Enter Rows = 7
            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 
    1 2 3 4 5 
      1 2 3 4 
        1 2 3 
          1 2 
            1

Right Pascal Triangle of Numbers

For more information, refer to the Python Right Pascal Triangle of Numbers.

def loopLogic(i, r):
    for j in range(1, i + 1):
        print(j, end=' ')
    print()

r = int(input("Enter Rows = "))

for i in range(1, r  + 1):
    loopLogic(i, r)
for i in range(r - 1, 0, -1):
    loopLogic(i, r)

Output

Enter Rows = 7
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 
1 2 3 4 5 
1 2 3 4 
1 2 3 
1 2 
1

Right Pascals Triangle of Multiplication Numbers Pattern

For more information, check out the Python Right Pascals Triangle of Multiplication Numbers.

def loopLogic(i, r):
    for j in range(1, i + 1):
        print(j * i, end=' ')
    print()

r = int(input("Enter Rows = "))

for i in range(1, r  + 1):
    loopLogic(i, r)
for i in range(r - 1, 0, -1):
    loopLogic(i, r)

Output

Enter Rows = 6
1 
2 4 
3 6 9 
4 8 12 16 
5 10 15 20 25 
6 12 18 24 30 36 
5 10 15 20 25 
4 8 12 16 
3 6 9 
2 4 
1

Right Pascals Triangle of Mirrored Numbers Pattern

For more information, check out the Python Right Pascals Triangle of Mirrored Numbers Pattern.

def loopLogic(i, r):
    for j in range(i, r + 1):
        print(j, end=' ')
    for k in range(r - 1, i - 1, -1):
        print(k, end=' ')
    print()

r = int(input("Enter Rows = "))

for i in range(r, 0, -1):
    loopLogic(i, r)
for i in range(2, r + 1):
    loopLogic(i, r)

Output

Enter Rows = 7
7 
6 7 6 
5 6 7 6 5 
4 5 6 7 6 5 4 
3 4 5 6 7 6 5 4 3 
2 3 4 5 6 7 6 5 4 3 2 
1 2 3 4 5 6 7 6 5 4 3 2 1 
2 3 4 5 6 7 6 5 4 3 2 
3 4 5 6 7 6 5 4 3 
4 5 6 7 6 5 4 
5 6 7 6 5 
6 7 6 
7

Python Program to Print Triangle Pattern of Alphabets

This section shows the various triangle patterns of alphabets or characters. For more information, see the Python Triangle Pattern of Alphabets.

r = int(input("Enter Rows = "))

alp = 65

for i in range(r):
    for j in range(r, i, -1):
        print(end = ' ')
    for k in range(i + 1):
        print('%c' %(alp + k), end = ' ')
    print()

Output

Enter Rows = 7
       A 
      A B 
     A B C 
    A B C D 
   A B C D E 
  A B C D E F 
 A B C D E F G

Downward Triangle Mirrored Alphabets Pattern

For more information, visit the Python Downward Triangle Mirrored Alphabets Pattern.

r = int(input("Enter Rows = "))

alp = 65

for i in range(r):
    for j in range(i, r):
        print('%c' %(alp + j), end = ' ')
    for k in range(r - 2, i - 1, -1):
        print('%c' %(alp + k), end = ' ')
    print()

Output

Enter Rows = 7
A B C D E F G F E D C B A 
B C D E F G F E D C B 
C D E F G F E D C 
D E F G F E D 
E F G F E 
F G F 
G

Inverted Triangle Alphabets Pattern

For more information, refer to the Python Inverted Triangle Alphabets Pattern.

r = int(input("Enter Rows = "))

alp = 65

for i in range(0, r):
    for j in range(r - 1, i - 1, -1):
        print('%c' %(alp + j), end = ' ')
    print()

Output

Enter Rows = 9
I H G F E D C B A 
I H G F E D C B 
I H G F E D C 
I H G F E D 
I H G F E 
I H G F 
I H G 
I H 
I

Triangle of Same Alphabets Pattern

For more information >> Python Triangle of Same Alphabets Pattern.

r = int(input("Enter Rows = "))

alp = 65

for i in range(r):
    for j in range(r - 1, i, -1):
        print(end = ' ')
    for k in range(i + 1):
        print('%c' %(alp + i), end = ' ')
    print()

Output

Enter Rows = 8
       A 
      B B 
     C C C 
    D D D D 
   E E E E E 
  F F F F F F 
 G G G G G G G 
H H H H H H H H

Triangle of Mirrored Alphabets Pattern

For more information, visit the Python Triangle of Mirrored Alphabets Pattern.

r = int(input("Enter Rows = "))

alp = 65

for i in range(r):
    for j in range(r - 1, i - 1, -1):
        print(end = ' ')
    for k in range(i + 1):
        print('%c' %(alp + k), end = '')
    for l in range(i - 1, -1, -1):
        print('%c' %(alp + l), end = '')
    print()

Output

Enter Rows = 9
         A
        ABA
       ABCBA
      ABCDCBA
     ABCDEDCBA
    ABCDEFEDCBA
   ABCDEFGFEDCBA
  ABCDEFGHGFEDCBA
 ABCDEFGHIHGFEDCBA

Triangle of Alphabets in Reverse Pattern

For more information, see the Python Triangle of Alphabets in Reverse Pattern.

r = int(input("Enter Rows = "))

alp = 65

for i in range(r - 1, -1, -1):
    for j in range(i):
        print(end = ' ')
    for k in range(i, r):
        print('%c' %(alp + k), end = ' ')
    print()

Output

Enter Rows = 11
          K 
         J K 
        I J K 
       H I J K 
      G H I J K 
     F G H I J K 
    E F G H I J K 
   D E F G H I J K 
  C D E F G H I J K 
 B C D E F G H I J K 
A B C D E F G H I J K

Downward Triangle Alphabets Pattern

For more information, visit the Python Downward Triangle Alphabets Pattern.

r = int(input("Enter Rows = "))

alp = 65

for i in range(r, 0, -1):
    for j in range(i):
        print('%c' %(alp + j), end = ' ')
    print()

Output

Enter Rows = 9
A B C D E F G H I 
A B C D E F G H 
A B C D E F G 
A B C D E F 
A B C D E 
A B C D 
A B C 
A B 
A