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in reply to (tye)Re3: (Golf): Sieve of Eratosthenes
in thread (Golf): Sieve of Eratosthenes

And almost a decade later I was randomly looking at this, and realized that it could be made shorter still. 
sub sieve3 {
    grep{@_[map$a*$_,2..@_/($a=$_)]=0if$_[$_]>1}@_=0..pop
}

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Never give up on that last optimization!

In Section Meditations