1 = 1 2
2 = 1 3
3 = 1 4
4 = 1 5
5 = 3 4
6 = 3 5
7 = 3 6
8 = 3 7
9 = 3 8
10 = 4 5
11 = 4 6
12 = 4 7
13 = 4 8
14 = 5 6
15 = 6 7
16 = 6 8
Counts 16
$VAR1 = {
          '6' => 2,
          '8' => 0,
          '4' => 0,
          '1' => 0,
          '3' => 1,
          '7' => 1,
          '2' => 0,
          '5' => 0
        };