def make_sequence(size, a, b):
    return [a*x + b for x in range(size)]

def get_primes_in_sequence(sequence):
    return [i for i in range(len(sequence)) if is_prime(sequence[i])]

def get_distance_between(numbers):
    return [numbers[i] - numbers[i-1] for i in range(1, len(numbers))]

def is_prime(n):
    if n <= 1: return False
    for divisor in range(2, int(n**0.5)+1):
        if n % divisor == 0: return False
    return True


sequence = make_sequence(10, 2, 1)
prime_indices = get_primes_in_sequence(sequence)
distances = get_distance_between(prime_indices)
print(prime_indices, distances)