Mathematics

Articles about numbers, structures, logic and mathematical concepts.

Articles in this category: 1129 Updated: April 29, 2026 Page 20 / 24

Right angle

Right angle (90°) — definition, notation, tests and uses

Right triangle

Right-hand rule

Rijndael key schedule

Rijndael (AES) key schedule

Ring (mathematics)

Ring theory

Ring theory (abstract algebra)

RMS

RMS — common meanings, history, and notable uses

Robert F. Coleman

Roman numerals

Roman numerals: system, history, and modern uses

Root of a function

ROT13

ROT13 — simple substitution cipher and its uses

Rounding

Rounding: methods, purpose, and impact on numerical results

RSA algorithm

RSA algorithm: public-key encryption, key generation, and history

Ruler

Ruler (measuring instrument): types, history, and common uses

Russell's paradox

S

S (letter) — nineteenth letter of the English alphabet

Sampi

Sample size

Sample size (statistics): definition, determination, and practical guidance

Scalar

Scale (ratio)

Scatter graph

Scatter graph (scatter plot)

Scheduling (computing)

Scheduling (computing): concepts, types, and algorithms

Scheme (programming language)

Scientific notation

Scientific notation: definition, format, uses and examples

Second

Second (unit of time)

Second normal form

Second Normal Form (2NF): Definition, Criteria, and Practical Guide

Selection sort

Self-similarity

Semi-major and semi-minor axes

Semi-major and semi-minor axes

Semicircle

Semiprime number

Sequence

Sequence

Sequence (ordered list of elements and mathematical concept)

An ordered list of items or events. In mathematics a sequence is a function with natural numbers as domain; types include finite/infinite, arithmetic/geometric, recurrent; importan

Series

Series (mathematical sums, convergence, and applications)

Set

Set theory

Seven Bridges of Königsberg

Sexagesimal

Sexagesimal (base 60) numeral system

SHA hash functions

SHA-1

SHA-1 (Secure Hash Algorithm 1)

Shape

Shape: definitions, classification, properties and applications

Shor's algorithm

Shor's algorithm: quantum integer factoring and cryptography impact

Short ton

Short ton: definition, conversions, history and uses

SI derived unit

Sicilian defence

Side

Side (geometry)

Siegfried Gottwald

Siegfried Gottwald (1943–2015), German mathematician and logician

Sieve of Eratosthenes

Sigma