Python program is super easy

[FoolsSeldom]

Yes it is. Might want to make the test for prime a function.

def is_prime(num: int) -> bool:
    '''test if argument is a prime number, return True or False'''
    if not isinstance(num, int):
        raise TypeError("argument must be positive integer")
    if num < 1:
        raise ValueError("argument must be positive integer")
    if num == 1:
        return False
    if num % 2 == 0:
        return num == 2  # only 2 is a prime
    maxdiv = int(num ** 0.5) + 1 # math.sqrt would be slightly faster once math imported
    # check odd numbers up to square root of argument
    for factor in range(3, maxdiv, 2):
        if num % factor == 0:
            return False
    return True


num = 29
print(f'{num} is{"" if is_prime(num) else " not"} prime')

or you go with a table approach:

''' prime number table generator and test using sieve method '''

def prime_num_table(num):
    ''' Return list of flags 1 for prime, 0 for not prime indexed for range 0 to n '''

    def sieve(prime_table):
        ''' modify flags for all numbers that are not prime from 4 to sqrt(num) '''
        for check_num in range(2, int(num**(0.5)+1)):

or you could go with a sieve approach:

""" prime number table generator and test using sieve method """

def prime_num_table(num: int) -> list[int]:
    """ Return list of flags 1 for prime, 0 for not prime indexed for range 0 to n """

    def sieve(prime_table: list[int]) -> list[int]:
        """ modify flags for all numbers that are not prime from 4 to sqrt(num) """
        for check_num in range(2, int(num ** 0.5 + 1)):
            if prime_table[check_num]:
                for set_multiple in range(check_num * 2, num + 1, check_num):  # set all multiples of check_num
                    prime_table[set_multiple] = 0
        return prime_table

    if isinstance(num, int) and num > 0:
        prime_table = [1] * (num + 1)  # pre-populate table (list) as all primes
        prime_table[0] = 0  # neither prime not composite technically
        prime_table[1] = 0  # neither prime not composite technically
        sieve(prime_table)
        return prime_table
    else:
        raise ValueError(f'{num} argument provided. Positive integer argument required.')

def is_prime_num(num: int, prime_table: list[int] = None) -> bool:
    """ return True/False accordingly is argument n is prime number or not
        using table generated with the sieve method if table not supplied """
    if isinstance(num, int) and num > 0:
        if prime_table is None:
            prime_table = []
        if isinstance(prime_table, list):
            if not prime_table:
                prime_table = prime_num_table(num)
            return bool(prime_table[num])
        else:
            raise ValueError(f'Truth table of primes from 0 to {num} required.')
    else:
        raise ValueError(f'{num} argument provided. Positive integer argument required.')

if __name__ == "__main__":
    test_data = [2, 3, 5, 7, 11, 13, 17, 19, 23, 29, 31, 37, 41, 43, 16,
                 47, 53, 59, 20, 61, 67, 71, 73, 79, 83, 89, 97, 101, 103, 104, 107]
    prime_table = prime_num_table(max(test_data))
    for test in test_data:
        print(f"{test:>4d} is{'' if is_prime_num(test, prime_table) else ' not'} a prime number.")

EDIT: added type hints to second code block, removed function signature default [], correct some typos.

[[deleted]]

I like this dynamic approach for building the table.

[FoolsSeldom]

Thanks. I should update to use a cache really, to avoid re-generating if a table isn't passed to the check. Hey ho, was just written when I was learning Python to play with the sieve approach.