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Python - Fastest Way to List Prime Numbers from 0 to a Number

🐍 Quickest way to list all Prime Numbers from 0 to a number taken from the user.

Solution

import math

def getprimes(n):

    primes = [2]

    for num in range(3,n+1,2):
        isprime = True
        numsqrt = int(math.sqrt(num)+1)

        for i in primes:
            if i<=numsqrt:
                if (num%i==0):
                    isprime = False
                    break
            else:
                break

        if isprime:
            primes.append(num)

    return primes

if __name__=='__main__':

    again = 'y'

    while again[0].lower()=='y':
        numto=int(input("Enter a number to find primes: "))
        print(getprimes(numto))
        again = input("Again? (y/n): ")

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