Gaurav has already won the Ballon d'Or 8 times, so he is really impressed with it (is he?). Gaurav has an array A containing N integers. Each element of this array is either 1 or 2. He wants to figure ...

We address two sets of long-standing open questions in linear algebra and probability theory, from a computational complexity perspective: stochastic matrix divisibility, and divisibility and ...

We define three hard problems in the theory of elliptic divisibility sequences (EDS Association, EDS Residue and EDS Discrete Log), each of which is solvable in sub-exponential time if and only if the ...