New “largest” prime number discovered!

Hold on to your hats!  A new “largest” prime number has been discovered.  Meet

257,885,161 – 1

How large is it?  Try to imagine this … a whopping 17,425,170 digits!  (Click here to see most of the number.)

This number is a special kind of prime number, called a Mersenne Prime.  First popularized by the French monk Marin Mersenne, primes of this form are generated using the formula 2p − 1 (where p is prime).  For example:  if p = 2, then 2– 1 = 3 or if p = 5, then 2– 1 = 31.  And, as you know, both 5 and 31 are prime numbers.

I know what you are thinking – I thought it was impossible to have a formula that generates primes.  Well, yes and no.  While there is no formula that will generate ALL prime numbers, there are many formulas that generate some primes.  Unfortunately, as with all prime formulas, even this formula doesn’t always work.  For example, if p = 11, then 211 – 1 = 2047.  2047 is a composite number with factors 23 and 89.

So, why bother with a formula that inconsistently generates primes?  Well, mathematicians are fun people.  And, like most people, they are attracted to big things – like big prime numbers.  Since this formula can generate some pretty massive numbers, the potential for monstrous-sized prime numbers exists.  And, what’s better than massive prime numbers?  Nothing!  In fact, some mathematicians are so obsessed with really big primes that they have started an internet search for big primes called GIMPS –  the Great Internet Mersenne Prime Search.

And, now, thanks to the GIMPS project, we have the 48th Mersenne prime … all 17,425,170 glorious digits.

Finally … a museum dedicated to math!

Well, it’s been a long time coming.  In a country that has museums dedicated to SPAM®, funerals and hobos, we finally have one dedicated to something much more interesting … mathematics!

Opening on 12/15/12 in New York City, the Museum of Mathematics will offer “dynamic exhibits and programs [that] will stimulate inquiry, spark curiosity, and reveal the wonders of mathematics. The museum’s activities will lead a broad and diverse audience to understand the evolving, creative, human, and aesthetic nature of mathematics.”

If you are interested in learning more about the museum or its founder, check out one of these websites:

I hope you get a chance to check it out!

The sounds of Pi

Ever wonder what Pi would sound like if it were played on musical instruments?  Well, here it is … the musical interpretation of Pi to 31 decimal places or 3.1415926535897932384626433832795.  I always knew that mathematics was visually beautiful, but I never imaged how beautiful it could sound.  Just breathtaking!  (Thanks to the musician Michael John Blake for taking the time to create it and to my colleague for finding the link for me.)

I wonder what the number e would sound like?

The World’s Hardest Easy Geometry Problem

Every once in a while a math problem takes the world by storm … at least the world of nerds.  About five years ago, the “World’s Hardest Easy Geometry Problem” hit the internet.  Not that this problem was new or unique.  After all, it has been around for hundreds of years.  However, with the speed and ease of communication of the internet, the problem spread like wildfire.  In fact, according to rumors, the problem was so addictive that the whiteboards in the offices of Google were filled with attempted solutions.  As the story goes, one employee said that the problem probably cost Google about a quarter of a million dollars in lost time.

What was the problem that people couldn’t stop thinking about?  Think you can solve it?  Enjoy … and no cheating!  (For a PDF version of the problem, click World’s Hardest Easy Geometry Problem.)

Did the Wizard cheat the Scarecrow?

It’s that time of year – the time of year I start talking about right triangles and the world-famous Pythagorean Theorem.  And, what discussion of the Pythagorean Theorem would be complete without telling my students about one the most important blunders in the “mathematical history” of Hollywood?

For those of you who may not know what I am talking about, you have to go back to 1939, to one of the most popular movies of all time, The Wizard of Oz.  If you remember the end of the movie, then you remember when the Scarecrow finally gets what he always wanted, a brain.  He is so excited to use his new brain, he decides to recite the Pythagorean Theorem.  The problem is he gets it wrong, completely wrong.  Below is his infamous statement: