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Each point in the list is assigned a unique name. In cases where no particular name arises from geometrical or historical considerations, the name of a star is used instead. For example, the 770th point in the list is named
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As of 6 February 2024, the list identifies over 61,000 triangle centers and is managed cooperatively by an international team of geometry researchers.
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37:. It started from a list of 400 triangle centers published in the 1998 book Triangle Centers and Central Triangles by Professor
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Similar, albeit shorter, lists exist for quadri-figures (quadrilaterals and systems of four lines) and polygon geometry.
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diagrams are provided for key points. The
Encyclopedia also includes a glossary of terms and definitions.
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55:. In GeoGebra, this encyclopedia is provided at fingertip by a special command.
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and its relation to lines joining other identified points. Links to
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Each point in the list is identified by an index number of the form
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symmedian point of the triangle formed by the centers of the three
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556:. Congressus numerantium. Utilitas Mathematica Publishing. 1998.
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This resource is seen as a pillar of the modern geometry, as in
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intersection of lines from each vertex to the corresponding
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74:. The information recorded about each point includes its
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694:Implementation of ETC points as Perl subroutines
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16:List of points considered center of a triangle
25:is an online list of thousands of points or "
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572:"Part 31: Centers X(52001) - X(54000)"
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553:Triangle Centers and Central Triangles
23:Encyclopedia of Triangle Centers (ETC)
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249:symmedian point of contact triangle
29:" associated with the geometry of a
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649:MathWorld--A Wolfram Web Resource
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51:"Encyclopedia of Triangle Cubics"
33:. This resource is hosted at the
705:Encyclopedia of Polygon Geometry
605:Encyclopedia of Triangle Centers
576:Encyclopedia of Triangle Centers
700:Encyclopedia of Quadri-figures
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510:Catalogue of Triangle Cubics
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735:21st-century encyclopedias
730:20th-century encyclopedias
230:intersection of the three
192:intersection of the three
154:intersection of the three
626:"TriangleCenter_Command"
532:Modern triangle geometry
526:The Secrets of Triangles
84:The Geometer's Sketchpad
35:University of Evansville
515:List of triangle topics
80:barycentric coordinates
725:Mathematical databases
175:circumscribed circle
696:by Jason Cantarella
680:"Kimberling Center"
645:"Kimberling Center"
643:Weisstein, Eric W.
478:Isoperimetric point
413:de Longchamps point
677:Weisstein, Eric W.
491:Equal detour point
597:Kimberling, Clark
568:Kimberling, Clark
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385:first and second
369:isodynamic points
367:first and second
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213:nine-point circle
207:nine-point center
49:Gibert, Bernard.
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720:Triangle centers
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668:Official website
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338:Feuerbach point
226:symmedian point
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101:Notable points
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608:. Retrieved
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610:February 6,
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465:Bevan point
281:Mittenpunkt
261:Nagel point
188:orthocenter
119:Definition
70:(1) is the
714:Categories
538:References
232:symmedians
685:MathWorld
287:excircles
194:altitudes
76:trilinear
630:Geogebra
601:"Thanks"
504:See also
150:Centroid
137:incircle
131:Incenter
72:incenter
31:triangle
156:medians
27:centers
487:(176)
474:(175)
378:(17),
360:(15),
269:point
94:Acamar
92:point
461:(40)
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326:Name
296:(10)
612:2024
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277:(9)
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127:(1)
116:Name
78:and
21:The
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Text is available under the Creative Commons Attribution-ShareAlike License. Additional terms may apply.