It is a challenge to define an uncountable set of real numbers that is dense in the real line and whose complement is also uncountable and dense. In this article we specify, for any positive integer k ...

The following dichotomy is established for any pair F, G of hereditary families of finite subsets of N: Given N, an infinite subset of N, there exists M an infinite subset of N so that either ...

Numbers comprise a string of digits that are used to represent various quantities and amounts. Each number designates the size of some quantity that is either large or small. Numbers can be of ...