def prime(n=100):
    chart = range(3,n+1,2)
    i,p = 0,3
    while p**2 < n:
        for x in chart[i+1:]:
            if x%p == 0:
                chart.remove(x)
        i += 1
        p = chart[i]
    if n == 9: chart.pop()
    chart.insert(0,2)
    return chart