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Iterating circum-medial triangles

Published online by Cambridge University Press:  21 October 2019

Hans Humenberger
University of Vienna, Faculty of Mathematics, Oskar-Morgenstern-Platz 1, A – 1090 Vienna, Austria e-mail:;
Franz Embacher
University of Vienna, Faculty of Mathematics, Oskar-Morgenstern-Platz 1, A – 1090 Vienna, Austria e-mail:;


When considering ‘convergence’ many people think of number sequences or contexts arising from calculus. But there are also interesting phenomena of convergence – easy to visualize – arising in elementary geometry. Some of them are so elementary that they can be dealt with at school, for instance an example of iteration that is described in [1, p. 171f] (see also [2, p. 59], [3, p. 222f] and [4, p. 42ff]).

© Mathematical Association 2019 

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