#!/usr/bin/perl -w 

use strict;

my @primes = (2, 3, 5, 7, 11, 13, 17, 19, 23, 29, 31, 37, 41, 43, 47);

sub listprimes {
    my $n      = shift; 
    my $i      = 0;
    my $answer = "";

    while($primes[$i] <= $n) {
         $answer .= " $primes[$i]"; 
         $i++;
    } 
    
    return $answer;
} 

sub random { 
    my ($a, $b) = @_;
    return int(rand($b - $a + 1)) + $a;
 }

my $a = random(10, 50); 
my $f = listprimes($a); 

print "$f\n";