x to the power of n is done via: $x ** $n or

sub x_power_n {
  my $x = shift;
  my $n = shift;
  my $result = $x;
  my $i = 1;
  while ($i < $n) {
    $result *= $x;
    $i++;
  }
  return $result;
}
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You need to do this, though, "infinite" times, reason why I provided a parameter to "stop" after a certain time.