Figure 14 . Examples of forests of trees. The (cid:12)gure on the left shows two branch-less trees, associated with masses m i and m respectively. Forests consisting of such branch-less trees will j ( = i ) 6 give non-zero contributions to the SQCDA partition function. The (cid:12)gure in the middle and on the right show trees with branches, or two trees associated to the same mass m i ; a forest that contains such trees does not contribute to the partition function by symmetry