🐍 Python Pattern Challenge — Day 14

Pattern printing is a great way to strengthen your Python logic, nested loops, conditions, spacing, and problem-solving skills. For Day 14, let's create a Number Pyramid Diamond where every row increases toward the center and then decreases symmetrically.

This pattern is interesting because each row contains numbers that increase toward the center and then decrease, creating a mirror-like structure.

Today's Challenge

Write a Python program to print:

           1
         1 2 1
      1 2 3 2 1
    1 2 3 4 3 2 1
      1 2 3 2 1
        1 2 1
          1

Best and cleanest code will be rewarded! 🏆

---

Solution 1 — Using Nested for Loops

n = 4

for i in range(1, n + 1):
    print("  " * (n - i), end=" ")

    for j in range(1, i + 1):
        print(j, end=" ")

    for j in range(i - 1, 0, -1):
        print(j, end=" ")

    print()

for i in range(n - 1, 0, -1):
    print("  " * (n - i), end=" ")

    for j in range(1, i + 1):
        print(j, end=" ")

    for j in range(i - 1, 0, -1):
        print(j, end=" ")

    print()

How it works

The first part creates the increasing half:

           1
        1 2 1
      1 2 3 2 1
    1 2 3 4 3 2 1

The second part reverses the rows:

      1 2 3 2 1
       1 2 1
         1
    
    
    
    
    

For each row, we use two loops:

for j in range(1, i + 1):

This prints the numbers in increasing order.

Then:

for j in range(i - 1, 0, -1):

prints them in decreasing order.

---

Solution 2 — Using a Single Main Loop

n = 4

for i in list(range(1, n + 1)) + list(range(n - 1, 0, -1)):
    print("  " * (n - i), end=" ")

    for j in range(1, i + 1):
        print(j, end=" ")

    for j in range(i - 1, 0, -1):
        print(j, end=" ")

    print()

How it works

Instead of writing two separate outer loops, we create the sequence:

[1, 2, 3, 4, 3, 2, 1]

Each value determines the size of that row.

For example, when:

i = 4

the inner loops produce:

1 2 3 4 3 2 1

This keeps the solution compact while still using clear logic.

---

Solution 3 — Using a Function

def number_diamond(n):

    for i in list(range(1, n + 1)) + list(range(n - 1, 0, -1)):

        print("  " * (n - i), end=" ")

        for j in range(1, i + 1):
            print(j, end=" ")

        for j in range(i - 1, 0, -1):
            print(j, end=" ")

        print()


number_diamond(4)

How it works

Putting the pattern inside a function makes it reusable.

Try:

number_diamond(5)

and you'll get a larger pattern.

This is a good way to combine functions + loops + pattern logic in Python.

---

⚡ Short & Clean Code

n = 4

for i in list(range(1, n + 1)) + list(range(n - 1, 0, -1)):
    print("  " * (n-i), *range(1, i+1), *range(i-1, 0, -1))

🔥 A single outer loop generates the complete number diamond.

---

🚀 Challenge Yourself

Can you modify this pattern:

• Take n using input()?
• Create the same pattern using a while loop?
• Replace numbers with letters?
• Create a hollow number diamond?
• Make the pattern work for any size?
• Print the numbers in reverse order?
• Create the same pattern using only one loop?

Drop your solution below! 👇

14 Days. 14 Patterns. Stronger Python Logic. 🐍🔥

Learn • Practice • Grow with CLCODING 🚀

100 Python One-Liners You Must Try