Since the membership of a sequence is almost never unambiguous, a heuristic is needed in order to partition the set of sequences into meaningful clusters. The set of all maximal cliques for a given constraint c guarantees us that every two members of a maximal clique will at least share a part of their sequence of length (|Ii| * c). Let Ic(Ci) denote that part of the query sequence that is overlapped by all sequences in clique Ci, i.e.,