Cool Facts

Are the reals countable?

John Gabriel (a non-mathematician) claims in his blog that the real numbers are countable. The author tries to enumerate the real numbers in the interval [0, 1) by writing out all those whose decimal representation has one digit after the dot (0.1, 0.2, …, 0.9), followed by those with two digits after the dot, then …

On a curious property of 3435

This is a neat little paper regarding the number 3435. Basically it has the following property: 3435 = 3^3 + 4^4 + 3^3 + 5^5 More interesting is that the only other number with this ‘property’ is the number 1. The property is what he calls a “Munchausen Number“. The preprint was written by Daan …

Guess 2/3 of the average

The game is… you compete against some other people each of you guess one number from [0, 100] compute 2/3rd’s of the average of the guessed numbers the winner is whoever is closest For example, if the numbers guessed are 7, 28, 53, 77, then the 2/3rd’s the average is: (0.66666) x ([7 + 28 …

How to: organize your digital library of papers

There are a few ways you can organize the digital papers you download. 1. One such way is using Zotero. Basically, Zotero [zoh-TAIR-oh] is a free, easy-to-use Firefox extension to help you collect, manage, and cite your research sources. 2. Another one is to use Mendeley. In addition to being multi-platform, it also has a …

Solving cryptograms in 10 simple steps

X NDPZ FSY’Z RBYZ ZS IA ZLAKA RLAY XZ LBMMAYP. Can you decode it? If not, let’s go through some general strategies that will help ðŸ˜€ 1. Words with one letter are either “A” or “I”. 2. A very frequent 3-letter word is “THE”. 3. There is an apostrophe then the letter after it is …

Divisibility Tricks

Is the number N divisible by…. 2? 3? 5? Everyone knows the first trick: N is divisible by 2 if its last digit is 0, 2, 4, 6, or 8 (that is, the last digit is even). Most people know the next trick: N is divisible by 3 if the sum of the digits is …

How to solve the sudokube

The Sudoku Cube is a ripoff of the Rubik’s Cube, where each face has the numbers 1-9 instead of colours. The goal: put the numbers 1-9 on each side with no repetition It was created in 2006 by some guy named Jay Horowitz in Ohio. You can buy it at Barnes and Noble and some …

List of famous mathematicians

Doing a school project on mathematicians? Don’t pick Einstein like your mom would… pick one from the following list instead. Then google their name + wikipedia, and tada, instant math project done! Hippias  Recorde, Robert Ferrari, Ludovico Viete, Francois Mahavira Bhaskara Fibonacci Stifel, Michael Tartaglia, Niccolo Cardano, Girolamo Ahmes Pythagoras Hippocrates Plato Ceulen, Ludolph van …

Google results based on number of o’s

Over on the xkcd forums there was a post about the number of google results for the word google with a varying number of “o’s”. Such as:ggglegogglegooglegooogle…goooooo *125 o’s in total*  oooogle The data yoteango collected is as follows: O’s    Search Results —————————-0      105,0001      1,500,0002      2,020,000,0003      342,0004      666,0005     …

The math behind low riding pants (how cool is it?)

In this post we learn all about the math behind low riding pants and how cool it really is. I decided to do a study just to see what the relationship was. I interviewed 13,532 people and showed them each 6 pictures of people wearing low riding pants. I then asked them to select a …