AOCP4

Generating All Combinations and Partitions

"We show how to sample acyclic digraphs uniformly at random through recursive enumeration. This provides an exact method which avoids the convergence issues of the alternative Markov chain methods. The limiting behaviour of the distribution of acyclic digraphs also allows us to sample arbitrarily large acyclic digraphs. Finally we discuss how to include various restrictions in the combinatorial enumeration for efficient uniform sampling of the corresponding graphs."

'We show that single-digit "Nishio" subproblems in nxn Sudoku puzzles may be solved in time o(2^n), faster than previous solutions such as the pattern overlay method. We also show that single-digit deduction in Sudoku is NP-hard.'

using a bit wise algorithm

see reviews/interviews.

"It is shown that at least 50% of the probability mass of a sum of independent Rademacher random variables is within one standard deviation from its mean. This lower bound is sharp, it is much better than for instance the bound that can be obtained from application of the Chebishev inequality..."

"An alternate form for the binomial tail is presented, which leads to a variety of bounds for the central tail. A few can be weakened into the corresponding Chernoff and Slud bounds, which not only demonstrates the quality of the presented bounds, but also provides alternate proofs for the classical bounds."