(economics, sociology) A group in a given population having an income within a specified range.

(algebraic geometry) A group that is an algebraic variety.

plural of group theory

(US) A small geographical unit that is part of the US censuses

(topology, category theory) A topological group that is isomorphic to the inverse limit of some inverse system of discrete finite groups; equivalently, a topological group that is also a Stone space.

Alternative form of yeargroup

(group theory) The group of automorphisms of a given set or other mathematical object, with the group operation being function composition.

(mathematics) For a field K, an abelian group whose elements are Morita equivalence classes of central simple algebras over K, with addition given by the tensor product of algebras.

(mathematics) A group that can be realized geometrically by sequences of reflections across the sides of a triangle.

(mathematics) The Chow groups of an algebraic variety over any field are algebro-geometric analogs of the homology of a topological space. The elements of the Chow group are formed out of subvarieties (so-called algebraic cycles) in a similar way to how simplicial or cellular homology groups are formed out of subcomplexes.