my $dna = join '', map { chomp; $_ } <DATA>;
my $template = ('AXA2X2A3X2' x (length($dna) - 2)) . 'AXA2XA';
my %count;
$count{$_}++ for unpack $template, $dna;
print "$_\t$count{$_}\n" for keys %count;
__DATA__
AAAAAAAACAAGAATACACAACCACGACTAGAGAAGCAGGAGTATATAATCATGATTCCACAACACCAGCATCCCCACCCCCGCCTCGCGACGCCGGCGT
CTCTACTCCTGCTTGGAGAAGACGAGGATGCGCAGCCGCGGCTGGGGAGGCGGGGGTGTGTAGTCGTGGTTTTATAATACTAGTATTCTCATCCTCGTCT
TGTGATGCTGGTGTTTTTATTCTTGTTTAACACAACCACTAGAGCAGTATATAATCCCACACCAGCCCCCCCTCGCGACGGCGTCTCTACTCCTGGGAGA
CGAGGATGCGCAGCGGCTGGGGAGGGGTGTAGTCTTATACTAGTATTCTCCTCGTCTTGTGATGCTGGACTGGGGTCGATCGTCGAAATCGGCTAGCTAA
AAAAAAACAAGAATACACAACCACGACTAGAGAAGCAGGAGTATATAATCATGATTCCACAACACCAGCATCCCCACCCCCGCCTCGCGACGCCGGCGTC
TCTACTCCTGCTTGGAGAAGACGAGGATGCGCAGCCGCGGCTGGGGAGGCGGGGGTGTGTAGTCGTGGTTTTATAATACTAGTATTCTCATCCTCGTCTT
GTGATGCTGGTGTTTTTATTCTTGTTTAACACAACCACTAGAGCAGTATATAATCCCACACCAGCCCCCCCTCGCGACGGCGTCTCTACTCCTGGGAGAC