regular commutator
21Orthogonal group — Group theory Group theory …
22Electricity meter — Typical North American domestic analog electricity meter …
23List of mathematics articles (C) — NOTOC C C closed subgroup C minimal theory C normal subgroup C number C semiring C space C symmetry C* algebra C0 semigroup CA group Cabal (set theory) Cabibbo Kobayashi Maskawa matrix Cabinet projection Cable knot Cabri Geometry Cabtaxi number… …
24Reflective subcategory — In mathematics, a subcategory A of a category B is said to be reflective in B when the inclusion functor from A to B has a left adjoint. This adjoint is sometimes called a reflector. Dually, A is said to be coreflective in B when the inclusion… …
25Hopf algebra — In mathematics, a Hopf algebra, named after Heinz Hopf, is a structure that is simultaneously a (unital associative) algebra, a coalgebra, and has an antiautomorphism, with these structures compatible.Hopf algebras occur naturally in algebraic… …
26PCC streetcar — Three PCCs on the San Francisco Municipal Railway s F line. An example of one double ended streetcar and two former SEPTA cars …
27Omega and agemo subgroup — In mathematics, or more specifically group theory, the omega and agemo subgroups described the so called power structure of a finite p group. They were introduced in (Hall 1933) where they were used to describe a class of finite p groups whose… …
28Algebraic K-theory — In mathematics, algebraic K theory is an important part of homological algebra concerned with defining and applying a sequence Kn(R) of functors from rings to abelian groups, for all integers n. For historical reasons, the lower K groups K0 and… …
29Invention of radio — Great Radio Controversy redirects here. For the album by the band Tesla, see The Great Radio Controversy. Contents 1 Physics of wireless signalling 2 Theory of electromagnetism …
30Hungary — This article is about the European country. For other uses, see Hungary (disambiguation). Republic of Hungary Magyar Köztársaság …
