# Issues

Published below are all past issues of *Principia*. Happy reading!

- Spring 2015
- Letter from the Editors
- The Group Structure of the Rubik's Cube - Richard Wong
- Error Bounds for Best-Arm Identification in Multi-Armed Bandits - Billy Fang
- The Mathematics Behind the Birthday Attack - Luke M. Kim
- The Cyclic Nature (and Other Intriguing Properties) of Descriptive Numbers - Trevor Scheopner
- Discrete Calculus and its Applications - Alec Payne
- Maximal Minors Preserving Two Local Connectivities - Feng Zhu
- Problem Corner
- Winter 2015–16
- The Crossing Number - Feng Zhu
- A Factorization Formula for Rational Functions and its Applications - Zihong Chen
- Applications of Information Theory: Statistics and Statistical Mechanics - Khizar Qureshi
- A Simplified Analysis To A Generalized Restricted Partition Problem - Abhinandan Dubey
- An Elementary Approach on Newman’s Proof of the Prime Number Theorem - Dimitrios Pagonakis, Evangelos Taratoris
- The Shifted Zeta Function at Integers - Zihong Chen
- Problem Corner
- Summer 2016
- Letter from the Editors
- How Many Circles Does It Take to ‘Subtend’ an Ellipse Externally? - Cassandra Lee
- Modeling Growth and Competition of Religions with Applications to Group Dynamics - Casey Cavanaugh, James Lamberti, Andres Salcedo
- The Poincaré–Hopf Index Theorem and the Fundamental Theorem of Algebra - Piotr Josevich
- A Function with the Darboux Property and Discontinuous at Every Point - Şerban Eugen Cicortaş
- Problem Corner