1. ## The Infinite In Haskell and Python

Exploring the use of coroutines and lazy evaluation to generate infinite structures in Haskell and Python.

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2. ## Understanding Recurrence Relations Using Automata, Python Code, And Javascript Visualizations

Recurrence relations are very often taught in first- or second-year computer science and discrete mathematics courses. This post takes a somewhat different and more visual approach to understanding linear recurrences and solving them by drawing the link between linear recurrences, automata, and matrices, using the problem of generating all domino-tilings of a board as the springboard. Code in Python and visualizations in JavaScript are used to demonstrate the ideas.

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3. ## Turing Recognizability of Turing Machines That Accept All Strings

A proof that the set of encodings of Turning machines that accept all strings is not Turing-recognizable.

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4. ## It From Bit - A Brief Exploration Of Some Ideas and Results From The Theory of Computation

A presentation I gave to a group of physics graduate students, as an introduction to some ideas and results in theoretical computer science.

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5. ## Understanding SAT by Implementing a Simple SAT Solver in Python

SAT is often described as the "mother of all NP-complete problems." This post goes over what SAT is and why it is considered to be so important. A simple SAT solver is implemented using Python in the process.

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6. ## So How Do You Actually Calculate The Fibonacci Numbers?

You have seen it as an example a million times. But do you know how to do it efficiently?

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7. ## Combinatorial Generation Using Coroutines With Examples in Python

Approaching combinatorial generation algorithms using coroutines, with examples in Python. Inspired by Knuth's work in his volume 4 of The Art of Computer Programming, as well as his "Deconstructing Coroutines" paper, co-written with Frank Ruskey.

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8. ## Multilinear Representation of Boolean Functions

Algorithm to compute the multilinear representation of a boolean function given its truth table.

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9. ## Line Intersecting Maximal Number of Circles (Circle "Stabbing" Problem)

Developing an algorithm to find a line that intersects a maximal number of circles, given a set of circles. Based on an ACM ICPC regional competition problem.

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10. ## Finding the Tangent Line to Two Circles Demonstrated Using JSXGraph

An HTML5 applet demonstrating step by step how to find tangent lines to two circles, using the JSXGraph framework.

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11. ## Thales Inscribed Angle Theorem Demonstrated Using JSXGraph

An HTML5 applet demonstrating the Thales inscribed angle theorem.

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12. ## Pattern Matching in Fibonacci Words (ACM ICPC World Finals 2012)

A discussion of calculating the number of occurrences of a given pattern in Fibonacci words, with a Java solution. Problem from the 2012 ACM ICPC world finals.

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13. ## Fibonacci Primitive Roots of Primes (Project Euler)

A problem on finding primes with Fibonacci primitive roots, from Project Euler and my Python solution.

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14. ## Basics of Cryptography Part I: RSA Encryption and Decryption

An introduction to RSA cryptography, with accompanying Python code implementing the basic algorithms used. A quick review of the number theory and group theory involved is given as well.

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15. ## Hundred Prisonors and a Room With a Light Switch

A hundred prisoners are given a challenge that might set them free. See if you can solve the puzzle involving a light switch and help them gain their freedom.

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16. ## Problem-Solving Lessons From George Pólya

What I learned from Newman's selections of Pólya's How to Solve It, the influential and beautifully written book on problem-solving techniques and heuristics.

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17. ## Interview Question: Fair and Unfair Coins and Bayes' Theorem (Groupon)

Groupon interview question to infer the probability of an event using Bayes' theorem.

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18. ## A Study of Python's More Advanced Features Part I: Iterators, Generators, itertools

A study of Python's iterators, generators and the itertools package, with ample (mostly) mathematical examples.

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19. ## Interview Question: Fairness from Unfairness (Groupon)

Groupon interview question to use an unfair coin to simulate a fair one. The question is the same as extracting randomness from an unfair Bernoulli process. A Python implementation is given.

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