crystallographic groups
A ‘herringbone' wallpaper
The symmetry group of the pattern in the figure is one such wallpaper group. It contains translations and glide reflections but has no non-trivial rotational symmetry. In all there are 17 wallpaper groups (up to isomorphism).
In three dimensions there are 230 crystallographic groups and in four dimensions there are 4783.
- divisor function
- divisor of zero
- dodecagon
- dodecahedron
- Dodgson, Charles Lutwidge
- domain
- domain
- domain
- dominated convergence theorem
- Donaldson, Simon
- dot
- dot product
- double dummy
- double factorial
- double integral
- double negation
- double point
- double precision
- double root
- double sequence
- double series
- double tangent
- double‐angle formula
- double‐angle formula
- dp