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> for i in range(2, int(n**0.5+1.5)):

As written, this code just tries all the integers (composite or not) up through sqrt(n). It's worth the extra lookup to only try the prime divisors:

> for i in range(2, int(n**0.5+1.5)):> if prime[i]:

Scott• 4 years ago> for i in range(2, int(n**0.5+1.5)):

As written, this code just tries all the integers (composite or not) up through sqrt(n). It's worth the extra lookup to only try the prime divisors:

> for i in range(2, int(n**0.5+1.5)):

> if prime[i]: