hdb recently pointed out that I had misremembered how the Sieve of Eratosthenes works so now I'm having another go. Not all that obfu'd but moderately golfed.

$m=250;for(2..$m){for($a=$_*2;$a<=$m;$a+=$_){$c[$a]++}print"$_,"x!$c[$_]}

In reply to This One's a Sieve by Schmunzie

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