Definition:Deltahedron/Mistake

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Source Work

1986: David Wells: Curious and Interesting Numbers:

The Dictionary
$8$


1997: David Wells: Curious and Interesting Numbers (2nd ed.):

The Dictionary
$8$


Mistake

A deltahedron is a polyhedron all of whose faces are triangular.


Correction

It is important to specify that the triangles in question are in fact equilateral.


This distinction is necessary, otherwise a subsequent statement:

... only $8$ of them are convex.

would be incorrect, as it would be possible to construct as many convex deltahedra as you like by constructing two pyramids whose bases are polygons with an arbitrary number of sides and placing them base to base to make a bipyramid.


Sources