Figure 8
Identifying Intersection sequences. Every path from left to right (starting at '-') in this tree represents a different node set N ⊆ V = {n1, n2, n3, n4, n5}. It is possible to search this tree and visit every node set N ⊆ V (exactly once). For example, follow the path {n1} → {n1, n2} → {n1, n2, n3} → {n1, n2, n3, n4} → {n1, n2, n3, n4, n5} → {n1, n2, n3, n5} → {n1, n2, n4} → {n1, n2, n4, n5} → {n1, n2, n5} → {n1, n3} → {n1, n3, n4} → {n1, n3, n4, n5} → {n1, n3, n5} → {n1, n4} → {n1, n4, n5} → {n1, n5} → {n2} → {n2, n3} → {n2, n3, n4} → {n2, n3, n4, n5} → {n2, n3, n5} → {n2, n4} → {n2, n4, n5} → {n2, n5} → {n3} → {n3, n4} → {n3, n4, n5} → {n3, n5} → {n4} → {n4, n5} → {n5}