$maxNumber   = 100;
$n = 10;

for ( $i=0; $i<$maxNumber; $i++ ) {
  $numbers[$i] = $i;
}

for ( $i=0; $i<$n; $i++ ) {
  $theNumber = int(rand(scalar(@numbers)) + 0.5);

  printf("$theNumber\n");

  splice(@numbers, $theNumber, 1);
}