Prime number programming in python

Enter a number: 13
13 is a prime number

Prime Number in Python using Function

In this program, We can also take the help of a user-defined function to check if a number is prime or not. A function is a block of code that performs a specific task.

# Python program to check if a number is prime or not def isPrime(num): #user-defined function if num > 1: for i in range(2, num//2): if (num % i) == 0: return False break else: return True else: return False # take inputs num = int(input('Enter a number: ')) # calling function and display result if(isPrime(num)): print(num, "is a prime number") else: print(num, "is not a prime number")

Enter a number: 250
250 is not a prime number

Program Using Recursion

We can also use the recursion technique to check if a number is prime or not in Python. A technique of defining the method/function that contains a call to itself is called recursion.

# Python program to check if a number is prime or not using recursion def isPrime(num, i = 2): #user-defined function if (num num): return True # Check next divisor return isPrime(num, i + 1) # take inputs num = int(input('Enter a number: ')) # calling function and display result if(isPrime(num)): print(num, "is a prime number") else: print(num, "is not a prime number")

Enter a number: 11
11 is a prime number

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Prime Numbers in Python

A Prime number can be explained as a finite number that is only divisible by 1 and by itself. It goes on like 2, 3, 5, 7, 11, 13, 17, 19, 23, 29, 31, 37, 41, 43, 47, 53, 59, 61, etc. This series of numbers can be recreated, and any given number can be identified if it is a prime number or not by implementing the logic in the python programming language. A few of the ways for this operation are using python libraries, coding with while loops, coding with loops and conditions, and using the lambda function.

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Prime Numbers: 2, 3, 5, 7, 11, 13, 17, 19, 23, 29, 31, 37, 41, 43, 47, 53, 59, 61, 67, 71, 73, 79, 83, 89, 97 etc.

Techniques to Implement Prime Number in Python

Prime numbers can be implemented in python by several techniques; four among them are explained below:

1. Using Lambda Function

# Prime determination method def Prime_series(number): for iter in range(2,number): if is_prime(iter) == True: print(iter,end = " ") else: pass number = int(input("Enter the input Range : ")) is_prime = lambda number: all( number%i != 0 for i in range(2, int(number**.5)+1) ) Prime_series(number) 

Explanation: This program determines the range of prime numbers using the lambda function technique; lambda represents an anonymous function or an orphan function. The program executes in such a manner that once a specific integer is keyed in by the user, then all the prime numbers within the range of 2 to key in the input will be generated and displayed.

Program Flow:

1. The input range is keyed in by the user; the python input function is used to receive the user’s input. The received input is handily cast into INT type.
2. The casted input is passed as an argument in a function call process. This function is responsible for triggering the lambda function for each and every integer in the given range of 2 to key in the input.
3. Hence the lambda function is called for each and every integer, and a prime check is carried on; the below-formulated logic is used for attaining this prime check, number%2 != 0

So as per the above-formulated logic, a Boolean value will be returned; the next step for each verified integer in the function is to check whether the returned Boolean is true or false, in the case when it falls true, then the corresponding variable is printed in the console.

2. Using for Loops and Conditions

# Prime determination method number = int(input("Enter the input Range : ")) for iter in range(2,number): for i in range(2,iter): if (iter%i==0): break else: print(iter) 

Explanation: This program determines the range of prime numbers using for loops and conditions; the program executes in such a manner that once a specific integer is keyed in by the user, then all the prime numbers within the range of 2 to keyed in input value will be generated and displayed.

Program Flow:

1. The input range is keyed in by the user; the python input function is used to receive the user’s input. The received input is handily casted into INT type.
2. Here, a nested loop is used to determine two integers; the first loop ensures to retrieve all the elements or integers falling within the range keyed. The second for-loop is responsible for determining the denominator of the prime check.
3. For every integer value denominated, if the outcome of the process is not equal to zero, then the integer handled is printed to the console.
4. This process is looped on and executed for every integer in the mentioned range of 2 to keyed in the input.

3. Using While Loops

range = int(input('Enter the integer range to find prime no: ')) number = 1 while(number 

import sympy start = int(input( " starting value : " )) end = int(input( " ending value : " )) list_prime_values = list(sympy.primerange(start,end+1)) print("All prime values in the range : " , list_prime_values)