In [47]:

    

a=[1]*10000


    

In [50]:

    

a[0]=a[1]=0


    

In [48]:

    

for i in range(2, 100):
    for j in range(2*i, 10000, i):
        a[j]=0


    

In [54]:

    

s = 0
for i in range(1, 10000, 10):
    if a[i] != 0:
        s += i
print s


    

    




1448386

In [55]:

    

b = range(10000)


    

In [57]:

    

b[1]=0


    

In [59]:

    

for i in range(2, 100):
    for j in range(2*i, 10000, i):
        b[j]=0


    

In [67]:

    

sum(b[i] for i in range(9, 10000, 10))


    

    
Out[67]:





1429557

In [68]:

    

sum(b[9::10])


    

    
Out[68]:





1429557

In [70]:

    

range(100)[9::20]


    

    
Out[70]:





[9, 29, 49, 69, 89]