Sperner's theorem is a result in combinatorics that deals with families of subsets of a finite set. Specifically, it states that if you have a set \( S \) with \( n \) elements, the largest family of subsets of \( S \) that can be chosen such that no one subset is contained within another (i.e.
Richard K. Guy (1916–2020) was a renowned British mathematician known for his contributions to various fields of mathematics, particularly in combinatorial game theory, number theory, and combinatorial geometry. He was a professor at the University of Calgary in Canada and had a long and prolific career in mathematical research and education. Guy is perhaps best known for co-authoring the influential book "Winning Ways for Your Mathematical Plays," which discusses strategies and theories related to combinatorial games.
As of my last update in October 2023, there is no widely recognized individual or entity named Jon Folkman in popular culture, history, or other notable fields. It's possible that Jon Folkman could refer to a private individual or a less well-known person in a specific context.
Van H. Vu is a mathematician known for his contributions to combinatorics, probability theory, and graph theory. He has worked extensively on problems related to random graphs, additive combinatorics, and extremal combinatorics. Vu has published numerous research papers and has collaborated with other mathematicians in the field. His work is influential in advancing the understanding of the connections between combinatorial structures and probabilistic methods.
Ebun Oni, which translates to "the gift of the spirit" in Yoruba, can refer to various meanings and contexts, often relating to cultural or spiritual themes. It may be associated with traditional Yoruba beliefs, where "Ebun" signifies a gift or blessing, and "Oni" suggests ownership or possession by the spirit.
The Stanley–Wilf conjecture is a statement in combinatorial mathematics concerning the enumeration of permutations and, more generally, the growth of certain classes of combinatorial objects. Specifically, it deals with the growth rate of the number of permutations avoiding a given set of patterns. Formulated in 1995 by Richard P.
Hermite interpolation is a method of interpolating a set of data points that not only matches the function values (as in polynomial interpolation) but also matches the derivatives at those points. This is particularly useful when you have information about not just the values of a function at certain nodes but also the behavior of the function (i.e., its slope) at those nodes.
The Generalized Integer Gamma Distribution is a statistical distribution that extends the traditional gamma distribution to encompass integer-valued random variables. While the classic gamma distribution is defined for continuous random variables, the generalized integer gamma distribution applies similar principles, allowing for the modeling of count data. ### Key Characteristics 1. **Parameterization**: The generalized integer gamma distribution is typically characterized by shape and scale parameters, similar to the standard gamma distribution.
The Kempner function, often denoted as \( K(n) \), is a function defined in number theory that counts the number of positive integers up to \( n \) that are relatively prime to \( n \) and also which contain no digit equal to 0 when expressed in decimal notation. This function is named after mathematician Howard Kempner. More formally, the Kempner function can be defined as follows: - Let \( n \) be a positive integer.
A Dynkin system (also known as a π-system or a Dynkin π-system) is a collection of sets that satisfies certain properties, making it useful in measure theory and probability. Specifically, a collection \( \mathcal{D} \) of subsets of a given set \( X \) is called a Dynkin system if it satisfies the following properties: 1. **Contains the entire set**: \( X \in \mathcal{D} \).
Kirkman's schoolgirl problem is a classic problem in combinatorial design and graph theory, posed by the mathematician Thomas Kirkman in 1850. The problem states the following: There are 15 schoolgirls who take part in a walking exercise. Each day, they walk in groups of three, and the condition is that each girl must walk with every other girl exactly once over a series of days. The challenge is to arrange these walks in such a way that the requirement is met.
A cold front is a boundary that forms when a cooler air mass moves in and displaces a warmer air mass. This movement is associated with a drop in temperature and can lead to various weather changes, including precipitation, changes in wind direction, and often, stormy conditions. ### Characteristics of Cold Fronts: 1. **Temperature Drop**: As the cold front moves in, temperatures typically decrease as the cooler air mass replaces the warmer air.
A sigma-ring (or σ-ring) is a mathematical structure that arises in the field of measure theory and set theory. Specifically, it is a collection of sets that is closed under certain operations, analogous to a σ-algebra but typically more general.
An "oval" in the context of projective geometry, specifically referring to a projective plane, is a particular type of geometric figure that has certain properties. In projective geometry, an "oval" is defined as a set of points with the following characteristics: 1. **Non-degenerate**: An oval is not degenerate, which means it does not collapse into a line or a point. It consists of multiple points.
Branch decomposition is a concept in graph theory that provides a way to represent a graph in a hierarchical structure, which is particularly useful for various applications, including optimization problems and parameterized complexity. ### Key Concepts of Branch-Decomposition: 1. **Definitions**: - A branch-decomposition of a graph \( G \) is a tree-like structure (called a branch tree) where each node is associated with subsets of vertices of \( G \).
Matroid girth is a concept in the field of matroid theory, which is a branch of combinatorics and discrete mathematics. In simple terms, the girth of a matroid refers to the length of the shortest circuit (or non-empty minimal dependent set) in the matroid. To provide some context: - A **matroid** is an abstract mathematical structure that generalizes the notion of linear independence in vector spaces.
A matroid oracle is a theoretical computational model used primarily in the study of matroid theory, which deals with combinatorial structures that generalize the notion of linear independence in vector spaces. The oracle serves as a black-box mechanism that helps efficiently answer certain queries related to the matroid.

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