How to quickly insert Double strike or Blackboard bold symbols in Word equations
To type the symbols in Double strike or Blackboard bold in the equation Microsoft Word (to insert equation into your text, click Alt+=), do one of the following:
- On the Equation tab, in the Symbols group,
click the More button:
In the top of list of symbols choose Scripts:
In the Scripts list, in the Double-Struck group, choose the symbol you prefer:
- Type \double + capital or lowercase letter:
Capital letters in the Double strike or Blackboard bold:
|Represents the algebraic numbers or affine space in algebraic geometry.
Occasionally represents the algebraic numbers, the algebraic closure of ℚ (more commonly written or ), or the algebraic integers, an important subring of the algebraic numbers.
|Sometimes represents a ball, a Boolean domain, or the Brauer group of a field.
|Represents the set of complex numbers.
|Represents the unit (open) disk in the complex plane (and by generalisation 𝔻n may mean the n-dimensional ball) — for example as a model of the Hyperbolic plane. Occasionally 𝔻 may mean the decimal fractions (see number) or split-complex numbers.
|Represents the expected value of a random variable, or Euclidean space, or a field in a tower of fields, or the Eudoxus reals.
|Represents a field. Often used for finite fields, with a subscript to indicate the order. Also represents a Hirzebruch surface or a free group, with a subset to indicate the number of generators (or generating set, if infinite).
|Represents a Grassmannian or a group, especially an algebraic group.
|Represents the quaternions (the H stands for Hamilton), or the upper half-plane, or hyperbolic space, or hyperhomology of a complex.
|The closed unit interval or the ideal of polynomials vanishing on a subset. Occasionally the identity mapping on an algebraic structure, or an indicator function, or the set of imaginary numbers (i.e., the set of all real multiples of the imaginary unit, more commonly indicated i ℝ).
|Occasionally represents the set of irrational numbers, R\Q (ℝ\ℚ).
|Represents a field, typically a scalar field. This is derived from the German word Körper, which is German for field (literally, "body"; cf. the French term corps). May also be used to denote a compact space.
|Represents the Lefschetz motive.
|Sometimes represents the monster group. The set of all m-by-n matrices is sometimes 𝕄(m, n).
|Blackboard bold capital N (for natural numbers set).
|Represents the octonions.
|Represents projective space, the probability of an event, the prime numbers, a power set, the irrational numbers, or a forcing poset.
|Blackboard bold capital Q (for rational numbers set).
|Represents the set of real numbers. ℝ>0 represents the positive reals, while ℝ≥0 represents the non-negative real numbers.
|Represents a sphere, or the sphere spectrum, or occasionally the sedenions.
|Represents the circle group, particularly the unit circle in the complex plane (and 𝕋n the n-dimensional torus), or a Hecke algebra (Hecke denoted his operators as Tn or 𝕋ℕ), or the tropical semi-ring, or twistor space.
|Represents a vector space or an affine variety generated by a set of polynomials.
|Occasionally represents the set of whole numbers (here in the sense of non-negative integers), which also are represented by ℕ0.
|Occasionally used to denote an arbitrary metric space.
|Represents the set of integers.
Some lowercase letters in the Double strike or Blackboard bold:
|May represent the differential symbol.
|Occasionally used for the mathematical constant e.
|Occasionally used for the imaginary unit.
See also this tip in French: Comment insérer rapidement des symboles double barre ou blackboard gras dans l'équation Word.