On Oblivious Branching Programs with Bounded Repetition that Cannot Efficiently Compute CNFs of Bounded Treewidth

In this paper we study complexity of an extension of ordered binary decision diagrams (OBDDs) called c-OBDDs on CNFs of bounded (primal graph) treewidth. In particular, we show that for each k ≥ 3 there is a class of CNFs of treewidth k for which the equivalent c-OBDDs are of size Ω(n k/(8c−4)). Moreover, this lower bound holds if c-OBDDs are non… CONTINUE READING