set of numbers
71Recursive set — In computability theory, a set of natural numbers is called recursive, computable or decidable if there is an algorithm which terminates after a finite amount of time and correctly decides whether or not a given number belongs to the set. A more… …
72Finite set — In mathematics, a set is called finite if there is a bijection between the set and some set of the form {1, 2, ..., n} where n is a natural number. (The value n = 0 is allowed; that is, the empty set is finite.) An infinite set is a set which is… …
73Arithmetical set — In mathematical logic, an arithmetical set (or arithmetic set) is a set of natural numbers that can be defined by a formula of first order Peano arithmetic. The arithmetical sets are classified by the arithmetical hierarchy.A function f:subseteq… …
74Definable set — In mathematical logic, a definable set is an n ary relation on the domain of a structure whose elements are precisely those elements satisfying some formula in the language of that structure. A set can be defined with or without parameters, which …
75Stirling numbers and exponential generating functions — The use of exponential generating functions or EGFs to study the properties of Stirling numbers is a classical exercise in combinatorics and possibly the canonical example of how symbolic combinatorics, the method that encapsulates the… …
76On Numbers and Games — is a mathematics book by John Horton Conway. The book is a serious mathematics book, written by a pre eminent mathematician, and is directed at other mathematicians. The material is, however, developed in a most playful and unpretentious manner… …
77Class (set theory) — In set theory and its applications throughout mathematics, a class is a collection of sets (or sometimes other mathematical objects) which can be unambiguously defined by a property that all its members share. The precise definition of class… …
78Partially ordered set — The Hasse diagram of the set of all subsets of a three element set {x, y, z}, ordered by inclusion. In mathematics, especially order theory, a partially ordered set (or poset) formalizes and generalizes the intuitive concept of an ordering,… …
79Gδ set — In the mathematical field of topology, a Gδ set, is a subset of a topological space that is a countable intersection of open sets. The notation originated in Germany with G for ( German : area) meaning open set in this case and δ for ( German :… …
80IP set — In mathematics, an IP set is a set of natural numbers which contains all finite sums of some infinite set.The finite sums of a set D of natural numbers are all those numbers that can be obtained by adding up the elements of some finite nonempty… …
