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" TITLE="">× ) ( ) ∨ (cube 6 square pyramids |- |bgcolor=#e7dcc3|Faces |18 |12 6 |- |bgcolor=#e7dcc3|Edges |colspan=2|20 |- |bgcolor=#e7dcc3|Vertices |colspan=2|9 |- |bgcolor=#e7dcc3|Dual |colspan=2|Octahedral pyramid |- |bgcolor=#e7dcc3|Symmetry group |colspan=2|B3, (), order 48 (), order 16 (), order 8 |- |bgcolor=#e7dcc3|Properties |colspan=2|convex, regular-faced |} In 4-dimensional geometry, the cubic pyramid is bounded by one cube on the base and 6 square pyramid cells which meet at the apex. Since a cube has a circumradius divided by edge length less than one,〔 sqrt(3)/2 = 0.866025〕 the square pyramids can made with regular faces by computing the appropriate height. The regular 24-cell has ''cubic pyramids'' around every vertex. The dual to the cubic pyramid is a octahedral pyramid, seen as an octahedral base, and 8 regular tetrahedral meeting at an apex. : == Related polytopes and honeycombs== A cubic pyramid of height zero can be seen as a cube divided into 6 square pyramids along with the center point. These square pyramid-filled cubes can tessellate three-dimensional space as a dual of the truncated cubic honeycomb, called a ''hexakis cubic honeycomb'', or pyramidille. 抄文引用元・出典: フリー百科事典『 ウィキペディア（Wikipedia）』 ■ウィキペディアで「cubic pyramid」の詳細全文を読む スポンサード リンク
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