Legendre's Quadratic Reciprocity Law

• RSA Encryption
• RSA Number
• Rubber-Sheet Geometry
• Rubik's Clock
• Rubik's Cube
• Rudin-Shapiro Sequence
• Rudvalis Group
• Rule
• Ruled Surface
• Rule of 72
• Ruler
• Ruler Function
• Ruling
• Run
• Runge-Kutta Method
• Runge-Walsh Theorem
• Running Knot
• Russell's Antinomy
• Russell's Paradox
• Russian Multiplication
• Russian Roulette
• Ryser Formula
• Rényi's Parking Constants
• Rössler Model
• Saalschützian