my @tri = ();
my %q = ();
for ($i = 1; $i <= 51; $i++) {
    my $m = (($i + 1) / 2);
    for ($j = 1; $j <= $m; $j ++) {
        my $v = 1;
        
        if ($i != 1) {
            if ($j == $m) {
                $v = $tri[$i - 1][$j - 1] * 2;
            } else {
                $v = $tri[$i - 1][$j - 1] + $tri[$i - 1][$j];
            }
        }
        
        $q{$v} = 1 if ((! $q{$v}) && is_squarefree($v));
        $tri[$i][$j] = $v;
    }
    print "Line $i\n";
}
$sum = 0;
foreach $k (sort keys %q) {
    $sum += $k;
    print "$k\n";
}
print $sum . "\n";

sub is_squarefree {
    my ($n) = @_;
    return 1 if ($n < 4);
    return 0 if ($n % 4 == 0);
    $toreturn = 1;
    #print ". $n\n";
    for ($p = 3; $p <= sqrt($n); $p += 2) {
        $toreturn = 0 if (isprime($p) && ($n % ($p ** 2)) == 0);
    }
    return $toreturn;
}

sub isprime {
    my $num = $_[0];
    my $val = 'prime';
    if ($num =~ /^\d+$/ && $num >= 2) {
        my $mod = 2;
        my $div = int sqrt $num;
        while ($mod <= $div) {
            ($num % $mod) == 0 ? ($val = 'composite', last) : $mod++;
        }
    } else { $val = 'neither'; }
    if ($val eq 'prime') {
      return 1;
    } else {
      return 0;
    }
}