Editing Talk:Johnson solid (section)

== "simple" Johnson solids? ==

28 of the Johnson solids are "simple".  Non-simple means you can cut the solid with a plane into two other regular-faced solids.  But it isn't clear which ones.  Anyone?  [[User:Dbenbenn|dbenbenn]] | [[User talk:Dbenbenn|talk]] 05:52, 26 Jan 2005 (UTC)

:Off the top of my head:
:*1-6 (pyramids, cupolae & rotunda) 
:*63 (tridiminished icosahedron - can't chop any further)
:*80 and 83 (parabidiminished & tridiminished rhombicosidodecahedra - ditto)
:*the "sporadics" 84-86 & 88-92, (87 is an augmented sporadic)  They have no relation to platonics or archimedeans.
:which makes 6+1+2+8 = 17.  There are other components from the platonic, archimedean, prisms and antiprisms that could arguably considered as needed for a building any of the J solids, but these are not "of the J solids".  I think I have all or most of the list here, given your defn - well short of 28.
:Where did you get 28?  ... ah I see it in the mathworld article.  Google throws up no other ref to "simple johnson solid".  I suspect Mathworld is wrong, probably in the defn of "simple"  --[[User:AndrewKepert|Andrew Kepert]] 07:58, 27 Jan 2005 (UTC)

::Okay, thanks.  That's disturbing if MathWorld is totally wrong here.  [[User:Dbenbenn|dbenbenn]] | [[User talk:Dbenbenn|talk]] 22:15, 27 Jan 2005 (UTC)

:Incidentally, the Wikipedia articles are using the term "[[elementary]]" instead of "[[simple]]," and upon incautious consideration I agree with Wikipedia's choice of terminology. &mdash;ajo, Apr 2005

: I added a table of images at the end. Very useful. 
: Probably the list should be moved to "List of Johnson solids", and then this article can be shorter.
: I'd like more statistics on these solids - Vertex, Edge, Face counts (and types of faces), Symmetry group. (I don't have this information) When this is available, making a data table would be more useful.
: [[User:Tomruen|Tom Ruen]] 19:48, 15 October 2005 (UTC)

:Actually, the Mathworld article was discussing all the simple convex regular-faced solids, including the simple Archimedean solids. There are 11 of these:
:
: tetrahedron
: dodecahedron
: truncated tetrahedron
: truncated cube
: truncated octahedron
: truncated cuboctahedron
: truncated dodecahedron
: truncated icosahedron
: truncated icosidodecahedron
: snub cube
: snub dodecahedron
:
: which when added to the 17 simple Johnson solids, make 28.
: [[User:Mongo62aa|Mongo62aa]] ([[User talk:Mongo62aa|talk]]) 03:07, 15 August 2010 (UTC)

:: The cube is excluded because ...? —[[User:Tamfang|Tamfang]] ([[User talk:Tamfang|talk]]) 16:50, 16 August 2010 (UTC)

::: Because the prisms and antiprisms are excluded, otherwise the list would be infinite in length. [[User:Mongo62aa|Mongo62aa]] ([[User talk:Mongo62aa|talk]]) 14:14, 17 August 2010 (UTC)