Improper Rotation
The Symmetry Operation corresponding to a Rotation followed by an Inversion Operation, also called aRotoinversion. This operation is denoted 
for an improper rotation by 
, so the CrystallographyRestriction gives only 
, 
, 
, 
, 
for crystals. The Mirror Plane symmetryoperation is 
, etc., which is equivalent to .
- Diagonal (Polygon)
- Diagonal (Polyhedron)
- Diagonal Ramsey Number
- Diagonal Slash
- Diagonal (Solidus)
- Diagonals Problem
- Diagram
- Diameter
- Diameter (General)
- Diameter (Graph)
- Diamond
- Dice
- Dichroic Polynomial
- Dido's Problem
- Diesis
- Diffeomorphism
- Difference
- Difference Equation
- Trigonometry Values Pi/4
- Trigonometry Values Pi/5
- Trigonometry Values Pi/6
- Trigonometry Values Pi/7
- Trigonometry Values Pi/8
- Trigonometry Values Pi/9
- Trigyrate Rhombicosidodecahedron