Interactive Cousin Prime Finder in Python

🧮 Find Cousin Primes with Python

🎯 What Are Cousin Primes?

Cousin primes are pairs of prime numbers that differ by exactly 4. Examples include (3, 7), (7, 11), and (13, 17). These pairs are part of the study of prime gaps and help us understand how primes are distributed.

💡 Interactive Approach

This Python script allows users to input an upper limit and dynamically find all cousin prime pairs up to that number.

💻 Python Code

def is_prime(n):
    if n < 2:
        return False
    for i in range(2, int(n**0.5) + 1):
        if n % i == 0:
            return False
    return True

def find_cousin_primes(limit):
    cousin_pairs = []
    for p in range(2, limit - 4):
        if is_prime(p) and is_prime(p + 4):
            cousin_pairs.append((p, p + 4))
    return cousin_pairs

def main():
    try:
        user_limit = int(input("Enter the upper limit to find cousin primes: "))
        cousins = find_cousin_primes(user_limit)
        print(f"\nCousin Prime Pairs up to {user_limit}:")
        for pair in cousins:
            print(pair)
    except ValueError:
        print("Please enter a valid integer.")

# Run the program
main()

Copy and Try it here!

📊 Sample Output

Input: 50

Output:

Cousin Prime Pairs up to 50:
(3, 7)
(7, 11)
(13, 17)
(19, 23)
(37, 41)
(43, 47)

🔍 Why It’s Useful

This interactive script is a great way to explore prime behavior and test hypotheses about prime gaps. It’s also a handy tool for CSIR NET preparation or any number theory project.

🌟 Final Thoughts

Try different limits and observe how cousin primes behave. Are they more frequent in smaller ranges? Do they thin out as numbers grow? This simple tool opens the door to deeper mathematical exploration.