Kaprekar’s constant

A student talked about Kaprekar’s constant (6174) during their my favorite presentation. Really cool. Steps (from wikipedia): Take any four-digit number, using at least two different digits. (Leading zeros are allowed.) Arrange the digits in descending and then in ascending order to get two four-digit numbers, adding leading zeros if necessary. Subtract the smaller number […]

Mandelbrot Fractal v2

I had so much fun with the original Mandelbrot program that I decided to see if I could improve it. I was amazed by how easily I was able to generate a fractal picture that looked exactly like other pictures online. I didn’t look at anyone else’s code, just went down the path and the amazing […]

Mandelbrot Fractal

I was inspired by a My Favorite presentation from a student on the Mandelbrot fractal. I played around for a half hour at school without a ton of success, but I sorted out the sticking points on the way home, and finished it up tonight. Amazingly simple (the code may not look simple, but it’s […]

Chaos Game v2

I prepared a small demonstration of the Chaos game for some math teachers. First we used transparencies, markers, dice, and rulers, but humans are mistake-prone and slow. To The Computer! I decided to experiment with the rules of the game to see where it’d go. Human Error What happens when you bring in a random amount […]

Two James Tanton Questions

It’s midterm week at school, and James Tanton threw out two interesting questions in two days. I spent a little time programming “solutions” to these problems (not solutions, just verifications for an infinitesimally small portion of the natural numbers). Problem One: Start with a prime, square it, and add 4. Repeat. (eg 3->13->173->…) Must eventually […]

Prime Matrix – Processing

Saw this tweet yesterday: All prime numbers between 2 and 2073600 mapped as pixels ARE THE MATRIX http://t.co/5skoRMc0gh — Kyle Hill (@Sci_Phile) January 14, 2014 Pretty cool. Josh Giesbrecht also did some great work with Mathematica to replicate the image. Thought that primes-looking-like-the-Matrix image might have been fake. Apparently not! (#Mathematica code included.) pic.twitter.com/LXFoTTNuyC — […]

Pebbling a Checkerboard Game (Or Chessboard)

I happened upon this tweet when I got to work this morning: Freeing imprisoned clones: finally a use for geometric series that isn't about computing interest http://t.co/FpJWxO73xI @numberphile #math — Matt Caicco (@MatthewJCaicco) December 20, 2013 So I watched the fantastic numberphile video Pebbling a Chessboard. I wanted to get the kids to play the game […]

Did the NSA make a major math breakthrough?

From The Daily Dot: To date, there is no known shortcut to quickly factor large integers into primes. It has never been proven that no such shortcut exists. We’ve just never found one. If the unfactorable nature of these large integers doesn’t interest you, consider that it has been the reason many of your most personal messages […]