We use exact enumeration to characterize the solutions of quadratic unconstrained binary optimization problems of less than 21 variables in terms of their distributions of Hamming distances to close-by solutions. We also perform experiments with the D-Wave Advantage 5. 1 quantum annealer. solving many instances of up to 170-variable. https://www.findingthestory.com/product-category/silicon-purge-plugs/