# Chronology of Updates

**Note**: I have placed chronology of updates for 1996, 1997, 1998, 1999, 2000, 2001 and 2002 into separate files. Starting with 1997, the most recent entries appear topmost. Besides providing an insight of this site's evolution, chronology updates may be used for word searches.

December 20, 2003 |
Poles, Polars and Quadrilaterals |

December 14, 2003 |
Twelve Matches Area Puzzle |

December 1, 2003 |
La Hire's Theorem |

November 28, 2003 |
Harmonic Ratio |

November 27, 2003 |
Straight Edge Only Construction of Polar |

November 22, 2003 |
Property of Points Where In- and Excircles Touch a Triangle |

November 11, 2003 |
Rusty Compass Construction of Equilateral Triangle |

November 3, 2003 |
Judd and Müller-Lyer Illusions |

October 31, 2003 |
Mazes |

October 22, 2003 |
Continuous Line Illusion |

October 21, 2003 |
Distorted Lines Illusion |

October 14, 2003 |
Delboeuf Illusion |

September 25, 2003 |
Ponzo Illusion II |

September 21, 2003 |
A Sampling from a Geometry Collection |

September 20, 2003 |
Review of *The Changing Shape of Geometry by Chris Pritchard* |

September 11, 2003 |
Inversion with Negative Power |

September 9, 2003 |
Squinting Eyes Theorem |

September 6, 2003 |
Friendly Kiepert's Perspectors |

September 4, 2003 |
Bottema's theorem |

September 2, 2003 |
Bride's Chair |

August 25, 2003 |
A significant upgrade of the Four 3's page |

August 17, 2003 |
Iterations on Euler Lines |

August 16, 2003 |
Euler Line Cuts Off Equilateral Triangle |

August 15, 2003 |
Cantor's Theorem |

August 14, 2003 |
Morley's Miracle: An Unexpected Variant |

August 11, 2003 |
Kanizsa Triangle |

August 2, 2003 |
Scintillating Grid Illusion |

August 1, 2003 |
Hermann Grid Illusion |

July 31, 2003 |
Simultaneous Contrast Illusion II |

July 27, 2003 |
4 Travelers problem, solution by M. Branchtein |

July 24, 2003 |
Constructing a triangle from its angle bisectors is in general impossible, by Vladimir Zajic |

July 21, 2003 |
Point common to two similar rectangles |

July 17, 2003 |
Problem in Three Squares |

July 5, 2003 |
Golomb's inductive proof of a tromino theorem |

July 2, 2003 |
Generating Functions |

June 29, 2003 |
Identities in the Multiplication Table |

June 28, 2003 |
Generating Functions |

June 27, 2003 |
Logistic Model applet |

June 1, 2003 |
Wittenbauer's Parallelogram and theorem |

May 10, 2003 |
The Lepidoptera of the Circles |

May 7, 2003 |
Proof #43 of the Pythagorean theorem |

May 4, 2003 |
Two Circles in a Square |

April 18, 2003 |
A Better Butterfly Theorem |

April 14, 2003 |
Averages in a sequence and Math Lotto by Cláudio Buffara and William McWorter, Jr. |

April 9, 2003 |
Proof #42 of the Pythagorean theorem |

April 8, 2003 |
Et tu ... |

March 19, 2003 |
Impossible Fork |

March 18, 2003 |
Revolving Circles Illusion |

March 6, 2003 |
Four Touching Circles |

March 4, 2003 |
Proof #41 of the Pythagorean theorem |

March 3, 2003 |
Ponzo Illusion |

March 2, 2003 |
Day's Sine and Simultaneous Contrast illusions |

March 1, 2003 |
Updated the Lagrange interpolation page |

February 28, 2003 |
Inversion |

February 20, 2003 |
Inversion: Reflection in a Circle |

February 19, 2003 |
Dual to Pappus' Theorem |

February 17, 2003 |
Poncelet's Porism |

February 9, 2003 |
Radical Axis of Circles Inscribed in a Circular Segment |

February 8, 2003 |
Circle Inscribed in a Circular Segment |

February 4, 2003 |
Isogonal Concurrency |

February 3, 2003 |
Maxwell's Theorem |

February 2, 2003 |
Four Incircles Theorem |

January 31, 2003 |
Equal Incircles Theorem |

January 30, 2003 |
Apollonian Gasket |

January 29, 2003 |
Soddy Circles and David Eppstein's Centers |

January 28, 2003 |
Thebault's Problem III |

January 27, 2003 |
Thebault's Problems I and II |

January 26, 2003 |
The Eyeball Theorem |

January 25, 2003 |
Mathematics in Pizzeria |

January 24, 2003 |
Incenters in Cyclic Quadrilateral |

January 21, 2003 |
Computer As a Magician |

January 19, 2003 |
Bachet's Magic Trick |

January 16, 2003 |
Gergonne's Magic Trick |

January 15, 2003 |
Magic in Square |

January 6, 2003 |
Simsons and 9-Point Circles in Cyclic Quadrilateral |

January 5, 2003 |
Remarkable Line in Cyclic Quadrilateral |

January 2, 2003 |
Newton's Theorem and Léon Anne's theorem |

January 1, 2003 |
Centroids in a Polygon |

|Contact|
|Front page|
|Contents|

Copyright © 1996-2018 Alexander Bogomolny