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© 1999-2019 Jürgen Köller
Hello, this also is a place to introduce myself a little.
Several email writers wanted to know whether I am a lazy student who doesn't finish his studying. This is a nice idea.
I was a teacher of mathematics and physics at a high school
(German: Gymnasium) up to summer 2000. Now I am retired. Maybe people of
my age solve crossword puzzles. I create web sites. I work on topics of
the recreational mathematics with great pleasure. I had no time to do so
as an active teacher. Sometimes I am astonished how many pages have already
This page is also available in German.