import math
def prime(n):
t=int(math.sqrt(n)+1)
if i==2:
return 1
for i in range(2,t+1):
if n%i==0:
return 0
return 1
result=0
for i in range(2,2000000):
if prime(i)==1:
result=result+i
print(result)
原文：http://www.cnblogs.com/lwjl/p/4239866.html