The compound of twenty octahedra is a geometric arrangement made up of 20 individual octahedral shapes. In a three-dimensional space, an octahedron is a polyhedron with eight faces, which are all equilateral triangles. When multiple octahedra are combined, they can create intricate structures. The compound of twenty octahedra often refers to a specific geometric construction where these octahedra are arranged in a symmetrical way.
The compound of two icosahedra is a geometric configuration formed by the intersection of two icosahedra. An icosahedron is a polyhedron with 20 triangular faces, and when two of them are combined, they can create a visually complex shape. In this specific compound, one icosahedron is typically inverted and placed within another. The resulting structure is symmetric and exhibits interesting geometric properties.
An elongated pyramid, often referred to as an "oblong pyramid," is a geometric figure that resembles a standard pyramid but has a rectangular or elongated base rather than a square one. The key characteristics of an elongated pyramid include: 1. **Base Shape**: Instead of a square base, it has a rectangular or oblong base, which means the length and width are different.
An elongated triangular bipyramid is a type of polyhedron that can be categorized as an Archimedean solid. It is formed by taking a triangular bipyramid and extending it along its vertical axis, effectively stretching it. To understand its structure, consider the following: - A standard triangular bipyramid is created by joining two tetrahedral pyramids base to base, which results in a shape that has six vertices, nine edges, and eight triangular faces.
The great deltoidal icositetrahedron is a type of convex polyhedron, more specifically one of the Archimedean solids. It is characterized by having 24 faces, of which 12 are regular octagons and 12 are equilateral triangles. Here are some key properties of the great deltoidal icositetrahedron: - **Vertices**: It has 48 vertices. - **Edges**: It features 72 edges.
Thymio is an educational robot designed to help users, especially children, learn programming, robotics, and problem-solving skills. Developed by the University of Geneva and the Thymio Project, Thymio features a user-friendly design and a variety of sensors that allow it to interact with its environment.
The great rhombidodecacoron is a convex uniform polychoron (a four-dimensional shape) in the context of higher-dimensional geometry. It is categorized under the family of Archimedean solids, specifically as a uniform spatial structure extending into four dimensions. This shape is distinguished by its vertices, edges, and faces, where it consists of 120 rhombic faces and 60 dodecahedral cells.
The great rhombic triacontahedron is a type of convex Archimedean solid, which is a class of polyhedra characterized by having regular polygons as their faces, with the same arrangement of faces around each vertex.
The great snub dodecicosidodecahedron is a type of Archimedean solid, which is a highly symmetrical, convex polyhedron with regular faces of more than one type. Specifically, the great snub dodecicosidodecahedron features: - **Faces**: It has a total of 92 faces, comprised of 12 regular pentagons, 20 regular hexagons, and 60 equilateral triangles.
A heptagonal bipyramid is a type of polyhedron that can be categorized as a bipyramid based on a heptagonal (7-sided) base. It is formed by taking a heptagon and creating two identical pyramids that are joined at their bases. ### Properties of a Heptagonal Bipyramid: 1. **Faces**: It has 14 triangular faces. Each of the sides of the heptagon contributes two triangles, one for each pyramid.
A gyroelongated cupola is a type of geometric shape that belongs to the family of Archimedean solids. It can be described as a convex polyhedron that combines features of two other solids: a cupola and a prism. Specifically, the gyroelongated cupola is formed by taking a cupola (which is created by connecting a base polygon to a top polygon through triangular faces) and then elongating it by joining two identical bases via a series of square faces.
A hexagonal bifrustum is a three-dimensional geometric shape that can be described as a truncated hexagonal prism. It is formed by taking a hexagonal prism and truncating (slicing off) the top and bottom sections at an angle, resulting in two hexagonal bases that are parallel to each other, with the top base being smaller than the bottom base.
The medial disdyakis triacontahedron is a geometric figure related to the disdyakis triacontahedron, which is one of the Johnson solids. A Johnson solid is a strictly convex polyhedron that has regular faces but is not uniform (meaning it does not have the same types of faces at each vertex). To break it down further: - The **disdyakis triacontahedron** itself has 32 faces: 30 triangular faces and 2 square faces.
The term "metabiaugmented dodecahedron" does not appear to correspond to any widely recognized geometric term or concept as of my last knowledge update in October 2023. However, it seems to imply a geometric figure related to the dodecahedron, a regular polyhedron with 12 pentagonal faces. The prefix "meta-" typically suggests some form of transformation or an additional layer regarding the original concept.
The term "parabiaugmented dodecahedron" refers to a specific geometric figure that is a type of convex polyhedron. It is derived from the dodecahedron, which is a Platonic solid with 12 regular pentagonal faces. The "parabiaugmented" part of the name indicates that the dodecahedron has been modified or augmented in a specific way.
The pentagonal orthobicupola is a type of convex polyhedron that is categorized among the Archimedean solids. It can be defined by its specific geometric properties as follows: 1. **Faces**: The pentagonal orthobicupola consists of 20 triangular faces and 12 regular pentagonal faces. 2. **Vertices**: It has a total of 60 vertices. 3. **Edges**: There are 90 edges in total.
The small ditrigonal dodecicosidodecahedron is a type of Archimedean solid, which is a convex polyhedron with identical vertices and faces composed of two or more types of regular polygons. Specifically, the small ditrigonal dodecicosidodecahedron has a face configuration of pentagons and hexagons.
A small dodecahemidodecahedron is a form of a polyhedron characterized by having 12 dodecahedral faces and 20 hexagonal faces, making it a member of the class of convex Archimedean solids. It is specifically classified as a "hemidodecahedron" because it has a symmetrical structure that can be thought of as a dodecahedron with additional vertices, edges, or faces.
The small dodecicosidodecahedron is one of the Archimedean solids and is classified as a polyhedron. More specifically, it is a convex polyhedral structure that consists of both regular and irregular faces.
The small icosihemidodecacron is a type of convex polyhedron that belongs to the family of Archimedean solids. Specifically, it is one of the deltahedra, which are polyhedra whose faces are all equilateral triangles. The small icosihemidodecacron has 20 faces, which are composed of equilateral triangles, along with 30 edges and 12 vertices.

Pinned article: Introduction to the OurBigBook Project

Welcome to the OurBigBook Project! Our goal is to create the perfect publishing platform for STEM subjects, and get university-level students to write the best free STEM tutorials ever.
Everyone is welcome to create an account and play with the site: ourbigbook.com/go/register. We belive that students themselves can write amazing tutorials, but teachers are welcome too. You can write about anything you want, it doesn't have to be STEM or even educational. Silly test content is very welcome and you won't be penalized in any way. Just keep it legal!
We have two killer features:
  1. topics: topics group articles by different users with the same title, e.g. here is the topic for the "Fundamental Theorem of Calculus" ourbigbook.com/go/topic/fundamental-theorem-of-calculus
    Articles of different users are sorted by upvote within each article page. This feature is a bit like:
    • a Wikipedia where each user can have their own version of each article
    • a Q&A website like Stack Overflow, where multiple people can give their views on a given topic, and the best ones are sorted by upvote. Except you don't need to wait for someone to ask first, and any topic goes, no matter how narrow or broad
    This feature makes it possible for readers to find better explanations of any topic created by other writers. And it allows writers to create an explanation in a place that readers might actually find it.
    Figure 1.
    Screenshot of the "Derivative" topic page
    . View it live at: ourbigbook.com/go/topic/derivative
  2. local editing: you can store all your personal knowledge base content locally in a plaintext markup format that can be edited locally and published either:
    This way you can be sure that even if OurBigBook.com were to go down one day (which we have no plans to do as it is quite cheap to host!), your content will still be perfectly readable as a static site.
    Figure 2.
    You can publish local OurBigBook lightweight markup files to either https://OurBigBook.com or as a static website
    .
    Figure 3.
    Visual Studio Code extension installation
    .
    Figure 4.
    Visual Studio Code extension tree navigation
    .
    Figure 5.
    Web editor
    . You can also edit articles on the Web editor without installing anything locally.
    Video 3.
    Edit locally and publish demo
    . Source. This shows editing OurBigBook Markup and publishing it using the Visual Studio Code extension.
    Video 4.
    OurBigBook Visual Studio Code extension editing and navigation demo
    . Source.
  3. https://raw.githubusercontent.com/ourbigbook/ourbigbook-media/master/feature/x/hilbert-space-arrow.png
  4. Infinitely deep tables of contents:
    Figure 6.
    Dynamic article tree with infinitely deep table of contents
    .
    Descendant pages can also show up as toplevel e.g.: ourbigbook.com/cirosantilli/chordate-subclade
All our software is open source and hosted at: github.com/ourbigbook/ourbigbook
Further documentation can be found at: docs.ourbigbook.com
Feel free to reach our to us for any help or suggestions: docs.ourbigbook.com/#contact