An algorithm is presented which finds (the size of) a maximum independent set of an n vertex graph in time O (2 0.276 n ) improving on a previous bound of O(2 n 3 ) .Expand

We show that the existence problem for tiling regions of the square lattice is NP-complete for general regions in the cubic lattice and for simply connected regions on the four-dimensional hypercubic lattice.Expand

We present a randomized distributed maximal independent set (MIS) algorithm for arbitrary graphs of size n that halts in time O(log n) with probability 1 − o(n−1), and only needs messages containing 1 bit.Expand

The game of Checkers can easily be generalized to be played on an N by N board and the complexity of deciding questions about positions regarded as a function of N is shown to be complete in exponential time.Expand