I'm not sure about your code - either the code is incomplete or the results you posted are not the actual results. Here is what I get :

D:\DATA\Projekte>type test.pl

use strict;
use vars qw(%HoA);
## increment the sequencer.
    $HoA{sequence} = 0 unless exists $HoA{sequence};
    my $i = ++$HoA{sequence};

    $HoA{test} = [ "aaa", "bbb", "ccc" ];

    print ("HoA test $i: " .   $HoA{test} ."\n" );
    print ("HoA test $i: " .   $HoA{test}->[0]  ."\n" );
    print ("HoA test $i: " .  @{ $HoA{test} } ."\n" );

D:\DATA\Projekte>perl -w test.pl
HoA test 1: ARRAY(0x1b9f0bc)
HoA test 1: aaa
HoA test 1: 3
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Your code shows HoA test 11, where I have HoA test 1 - either your sequence gets set earlier, or your results don't result from the code you showed. From the results you posted, I'd guess that the code that produced these results simply had an empty array.

perl -MHTTP::Daemon -MHTTP::Response -MLWP::Simple -e ' ;    # The  
$d = new HTTP::Daemon and fork and getprint $d->url and exit;#spider
($c = $d->accept())->get_request(); $c->send_response( new   #in the
HTTP::Response(200,$_,$_,qq(Just another Perl hacker\n))); ' #  web
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