>>> from math import sqrt
>>> n = 100
>>> sqrt_n = int(sqrt(n))
>>> no_p = [j for i in range(2,sqrt_n) for j in range(i*2, n, i)]
>>> no_p
[4, 6, 8, 10, 12, 14, 16, 18, 20, 22, 24, 26, 28, 30, 32, 34, 36, 38, 40, 42, 44, 46, 48, 50, 52, 54, 56, 58, 60, 62, 64, 66, 68, 70, 72, 74, 76, 78, 80, 82, 84, 86, 88, 90, 92, 94, 96, 98, 6, 9, 12, 15, 18, 21, 24, 27, 30, 33, 36, 39, 42, 45, 48, 51, 54, 57, 60, 63, 66, 69, 72, 75, 78, 81, 84, 87, 90, 93, 96, 99, 8, 12, 16, 20, 24, 28, 32, 36, 40, 44, 48, 52, 56, 60, 64, 68, 72, 76, 80, 84, 88, 92, 96, 10, 15, 20, 25, 30, 35, 40, 45, 50, 55, 60, 65, 70, 75, 80, 85, 90, 95, 12, 18, 24, 30, 36, 42, 48, 54, 60, 66, 72, 78, 84, 90, 96, 14, 21, 28, 35, 42, 49, 56, 63, 70, 77, 84, 91, 98, 16, 24, 32, 40, 48, 56, 64, 72, 80, 88, 96, 18, 27, 36, 45, 54, 63, 72, 81, 90, 99]
>>>
Problem: In der Liste der nicht-Primzahlen gibt es zahlreiche Doppeleinträge!