the bounds obtained by rigorous methods in Fig. 1. Lower bounds are obtained by showing that some analyzable algorithms, such as unit clause propagation[6] find SAT solutions with a finite probability=-=[57]-=-. Upper bounds use the fact that the probability of finding a satisfying assignment is bounded by the expected number of solutions. Refined versions of this argument[41, 90] partially eliminate the poaster algorithm. Pina et al. [13] improved Buny