The busy beaver is an example of a function which is not computable. It is based on a particular class of Turing machines, and is defined as the largest number of 1's that ca...
We consider the new problem of determining the number of partitions of a number into a fixed number k of squares, and find explicit formulae in the cases k = 2, 3, 4. Classificati...
For applications to cryptography, it is important to represent numbers with a small number of non-zero digits (Hamming weight) or with small absolute sum of digits. The problem of ...
We consider vertex coloring of an acyclic digraph G in such a way that two vertices which have a common ancestor in G receive distinct colors. Such colorings arise in a natural wa...
Frequent structure mining (FSM) aims to discover and extract patterns frequently occurring in structural data, such as trees and graphs. FSM finds many applications in bioinformat...