Definition:Deltahedron/Mistake
Jump to navigation
Jump to search
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
- 1986: David Wells: Curious and Interesting Numbers ... (previous) ... (next): $8$
- 1997: David Wells: Curious and Interesting Numbers (2nd ed.) ... (previous) ... (next): $8$