Polynomial Ring
The Ring 
of Polynomials in a variable 
.
- Ramsey Number
- Ramsey's Theorem
- Randelbrot Set
- Random Distribution
- Random Dot Stereogram
- Random Graph
- Random Matrix
- Random Number
- Random Percolation
- Random Polynomial
- Random Variable
- Random Walk
- Random Walk--1-D
- Random Walk--2-D
- Random Walk--3-D
- Range (Image)
- Range (Line Segment)
- Range (Statistics)
- Rank
- Rank (Group)
- Rank (Quadratic Form)
- Rank (Sequence)
- Rank (Statistics)
- Rank (Tensor)
- Ranunculoid