Here is one of 68 characters in length: 
sub p{my@x;map{my$c=$_;$_%$c||++$x[$_]for@_}@_=2..pop;grep$x[$_]==1,0.
+.$#x}

[download]
UPDATE: And another of 65: 
sub p{@_=2..pop;my$c;while($_[$c]){@_=($_[$c],grep$_%$_[$c],@_);$c++}@
+_}

[download]
UPDATE: And another of 60: 
sub p{@_=2..pop;my$c;@_=($_[$c++],grep$_%$_[$c-1],@_)while$c<@_;@_}

[download]
UPDATE: And another of 40 (but I fear it strays from the rules...): 
sub p{grep{my$c=$_;$#_==grep$c%$_,@_}@_=2..pop}

[download]


japhy -- Perl and Regex Hacker

In reply to Re: (Golf): Sieve of Eratosthenes by japhy
in thread (Golf): Sieve of Eratosthenes by tilly

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