# Solution Exercise 755: python algorithm to find the list of all prim number contained in given intervall

Sep 17, 2020

#### Exercise 755

Write a Python algorithm in the form of a function which takes as argument an integer n and which returns the list of all the prime integers contained in the interval [n, 2n] Example for n = 9, the function returns the list of the all prim numbers contained in the interval [9, 18] which is L = [11, 13, 17].

#### Solution

``# creating function to test if given number is prim or notdef testPrim(m):    # Initializing number of divisors    numberDivisors = 0        # while i is divisor of m we increment numberDivisors    for i in range(1 , m + 1):        if(m%i == 0):            numberDivisors = numberDivisors + 1                # a number is prime if and only if it has two divisors, 1 and itself    if (numberDivisors == 2):        return True    else:        return False    def listPrim(n):    # initializing the list of prim numbers    L = []    for i in range(n , 2*n):        if testPrim(i):            L.append(i)    return L# Testing algorithmprint("The list of all prim numbers in [9 , 18] is : " , listPrim(9))``

Younes Derfoufi
my-courses.net