# Xah Math

Math related things i've written.

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A Visual Dictionary of Special Plane Curves

Gallery of Surfaces

Wallpaper Groups

Math Graphics Gallery

Intro to POV-Ray

Math Software

Transformation on the Plane

Intro to Real Projective Plane

Notes on A New Kind of Science

Escher Chameleon Polyhedron

Polyhedra Sculptures

Polyhedra Chocolate

Number Of Ways To Loop n Points

Paper Folding Boats

Mathematica Logo History

Magic Polyhedrons

Beauty of Roots

Reading Notes on “The Shape of Space”

What is Technical Drawing, Descriptive Geometry, Projective Geometry, Linear Algebra

Knitting, Chinese Knots, Braid Theory

Celtic Knots, Truchet tiles, Combinatorial Patterns

Math Tiling Automata Morph

Go Board Game on Hexagonal and Triangular Grids

A Fantastic Auto-stereogram

Visual Illusions

Tilings and Patterns Book

Projective Illusion Stereographic Projection 3D-Printed Physical Model

Tron Lightcycle Optimal Strategy

Ladybug Video Game, Optimal Strategy

Maze and Math in Video Games

Math Art of Hop David

## Math Books

## Math Notation, Syntax, Formal Language

- Math Notation, Computer Language Syntax, and the “Form” in Formalism
- The Codification of Mathematics

## Social

- Grigori Perelman and Money
- Math Prizes and Nobel Ignobility
- Alexander Grothendieck = Obi-Wan
- Math Politics: Simon Plouffe and nth Digit Formula of π
- Twin Prime Conjecture Breakthru: Yitang Zhang
- Martin Gardner (1914 to 2010)
- Mathematician Marijke Van Gans Died (1955 to 2009)
- Russell Towle Died (1949 to 2008)
- Robby Villegas Died (1968 to 2010)
- What and Why Mathematics?

## Misc Random Notes

- The Geometric Significance of Complex Conjugate
- Multiplication and Multiplicative Identity
- Understanding Complex Numbers
- John Baez on Octonion 📺
- The Significance of Complex Numbers: Frobenius Theorem
- 1+2+3+4+… = -1/12, Ramanujan's Sum 📺
- Adaptive Sampling, Plotting Math Curve

- the Nature of Associative Property of Algebra
- Euler Angles Can Cause Gimbal Lock, But Not Quaternions
- Bird Flight V Formation as Geometry Problem of Max Visual Contact
- the Nature of Linear Transformation
- What's the Nature of Eigenvector?
- On the Nomenclature of Eigenvector and the Igon Value Problem
- What's Difference Set of a Group

- What is Riemann Surface? Understanding the Concept Without Math
- Klein Bottle Checker Board Paradox
- Learning Notes Of Symmetric Space and Differential Geometry Topics
- Reading Notes on Nicolas Bourbaki
- What is Quadratic Form in Math?
- Space-Filling Curve
- Reading Notes on Tilings and Patterns
- Xah Math Notes

- Teacup Recursion
- Conway's Game of Life Recursively Defined
- Mandelbrot Set Explained (no complex number needed)

- English/Chinese Math Terminology 中/英 数学术语
- Orbits in Juggling's Siteswap Notation
- Bejeweled Blitz Strategy as Math
- Geometry: Ellipses, Linkages, Solids of Constant Width 📺
- Plants vs Zombie; Thoughts on Strategy and Game Formulation
- Why Are Scores in Video Games Mega Huge?

- What's a Year? Why Not Just 100 Days?
- What Voting Systems are There?
- Modeling Math Problem Into a Question in Formal Language

- HP-28S Advanced Scientific Calculator
- What's the Latest and Greatest in Calculators?
- 3D Visualization Design

- Math: ID System, Number Base vs Number of Digits
- math simulation ideas
- ants, insects, decentralized systems
- Notes On Plane Curves and Proofs
- Principia Mathematica

- Theory Of Equations
- Review of Khan Academy by Xah Lee
- The Logical Levels of Interpretation
- Math Formula For Beauty
- Dead Reckoning in a Non-Orientable 3D Space
- Math, Algebra: On the Phraseology of X Over K
- Schmidt Arrangement, Algebra Integer, Gaussian Integer, Eisenstein Integer, Modular Group
- Extending the Euclidean Plane: Riemann Sphere and Real Projective Plane
- Combinatorics, Algorithm, and Humanity
- Go Game: Google AlphaGo vs Lee Sedol
- Geometer's Sketchpad Closed Shop?
- Xah's Top 10 Math Wonders

Why Are Textbook So Expensive?

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