elongated pyramid

{{short description|Polyhedron formed by capping a prism with a pyramid}}

{{Infobox polyhedron

| image = Elongated pentagonal pyramid.png

| caption = Example: pentagonal form

| type =

| euler =

| faces = {{mvar|n}} triangles
{{mvar|n}} squares
1 {{nowrap|{{mvar|n}}-gon}}

| edges = {{math|4n}}

| vertices = {{math|2n + 1}}

| vertex_config =

| schläfli =

| wythoff =

| coxeter =

| symmetry = {{math|C_nv, [n], (*nn)}}

| rotation_group = {{math|C_n, [n]⁺, (nn)}}

| surface_area =

| volume =

| dual = self-dual

| properties = convex

}}

In geometry, the elongated pyramids are an infinite set of polyhedra, constructed by adjoining an {{nowrap|{{mvar|n}}-gonal}} pyramid to an {{nowrap|{{mvar|n}}-gonal}} prism. Along with the set of pyramids, these figures are topologically self-dual.

There are three elongated pyramids that are Johnson solids:

• Elongated triangular pyramid ({{math|J{{sub|7}}}}),
• Elongated square pyramid ({{math|J{{sub|8}}}}), and
• Elongated pentagonal pyramid ({{math|J{{sub|9}}}}).

Higher forms can be constructed with isosceles triangles.