# Joan Folguera Farré

I like to be dynamic with math. In fact, I am the secretary of
LLEIMAT, the Association of Mathematics Teachers of FEEMCAT, a group
of the Organization for the Teaching of Mathematics in Catalonia and
an active member of the Museum of Mathematics of Catalonia. Last but
not least, I do workshops, presentations, talks and exhibitions all
over Catalonia.

This polyhedron is formed by a tetrahemihexahedron and the hole is
filled with dented cubes. It has the peculiarity that the total
surface is invariant. Get to fill the whole hole but the surface
is the one that was originally there: the side area of the inner
pyramid green