prime in pugs

joe@flatpan:~$ time pugs prime.p6
5323
705

real    0m26.681s
user    0m26.390s
sys    0m0.080s

joe@flatpan:~$ cat prime.p6
my @primes=(2,3);
for 1..20->$k {
  for @primes[$k-1]**2+1 .. @primes[$k]**2-1 {
    push @primes, $_ if ($_ % none @primes[0..$k])==0
  }
};
say @primes.max;
say @primes.elems