Hi all! I'm a Perl newb and I'm writing a Sieve of Eratosthenes. I know users have GOLF'd it on this site but GOLFing is way down the road for me. Anyway, here's what I have: 
#!/usr/bin/perl

print "Show primes up to: ";
chomp($max = <>);

@n = (2..$max);
@f = (2..sqrt(@n));

foreach $i (@f) {
        @e = grep {$_ % $i != 0}  @n;
        @n = ();
        @n = @e;
}

print "@n\n";

./sieve.pl
Show primes up to: 21
5 7 11 13 17 19

[download]
Pretty good! Wait...it is cutting out the 2 and 3. And if I go higher: 
./sieve.pl
Show primes up to: 31
7 11 13 17 19 23 29 31

[download]
That's no good. Can someone help show me what i'm missing? Not looking for an answer, just looking for a shove in the right direction. Any help is appreciated.

In reply to What am I missing? by neo_

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