first 100 prime numbers python list comprehension

Now if you input a prime number it returns : Īnd any other number such as 20 :

If is_prime(a)=True: #if the inputted number is prime it automatically appends that number to the list and breaks since prime numbers don't have any other factorsĭef remove_duplicates(values): #here it checks for duplicates #print(n) #otherwise it prints out the number since it is a prime number #print(n) #if one of the factors is 2 it prints it because it is a prime number When you input a prime number it returns a blank array.

If we run this and I input 10 it returns this : Print(n) #otherwise it prints out the number since it is a prime numberįor n in b: #iterates through the list of factors and checks if they are prime If n % 2 = 0 or n <= 1: # if it is less than one or is a factor of 2 it returns false and does nothingįor divisor in range(3, sqr, 2): #checks for other divisors Print(n) #if one of the factors is 2 it prints it because it is a prime number Instead of printing it you could also append it to another list by replace the print(n) with something else. Thanks to Jonathan Gregory for leading me most of the way to this approach.Here you can print the list of factors and then iterate through the list of factors and this program will print out the ones that are prime. On my machine, I can keep going until some N between 300000 before I run out of memory. Whereas the 'adding the last two values' approach can generate higher values for larger N. Gives for me: OverflowError: (34, 'Numerical result out of range') If, however, you don't want all of the values then the explicit form could be much faster, but it does suffer from overflow for some N between 10: n = 2000 This is faster than the explicit form for generating all of the values up to N. Here's a one-line list comprehension solution that avoids the separate initialization step with nested ternary operators and the walrus operator (so needs Python 3.8), and also avoids the rapid onset of overflow problems that the explicit form can give you (with its **n component): [ Storing the last 2 terms of the sequence during calculation of the sequence is a side-effect, therefore a list comprehension is ill-suited to the task on its own.Ī safe way around this would be to make a closure generator (essentially a generator with some associated private state) that can be passed to the list comprehension such that the list comprehension does not have to worry about the details of what's being stored: def fib_generator(n): A list comprehension is designed to create a list with no side effects during the comprehension (apart from the creation of the single list). The conventional way to calculate the nth term of the fibonacci sequence is to sum the n-1 and n-2 terms, as you're aware.

First 100 prime numbers python list comprehension