As well as the perturbation cutoffs and temperature used in the BH acceptance test, the behavior of the combined, QR-BH, search is influenced by the number of quasi-random seed structures and the length of each BH trajectory. Unless otherwise stated, all BH trajectories in a search were run for the same, fixed total number of steps. The job of the quasi-random seeds is to sample the energy landscape widely and evenly, while each local region is then efficiently explored in the BH search. Conceptually, the most efficient search could be achieved when each BH trajectory samples a separate region of the energy landscape and these local regions combined make up the entire energy landscape.