Pascal’s, and Rascal’s, Triangles

Pascal’s Triangle is one of the most well-known mathematical constructions in human history.  Named after Blaise Pascal, the triangle is rich in patterns and famous number sequences.  The first five rows are shown below.

Pascal triangle five rows

There are many ways to produce Pascal’s Triangle, but the typical way is to define every number as the sum of the two numbers above it:  the one above on the right and the one above on the left.  If there isn’t a number, then just use zero.  For example, 4  = 1 + 3, and 6 = 3 + 3.

The ubiquity of Pascal’s Triangle makes it even more remarkable that a group of three junior high school students have recently collaborated on a paper published in the College Mathematics Journal that uses the famous triangle to find a new number pattern!

Apparently the story begins with one of the students confounding their teacher by insisting that the fifth row of the triangle should be

rascal numbers

Despite the teacher’s attempts to “correct” them, the students produced a valid recursive relationship for the new triangle, which they describe as ( East * West + 1 ) / North.  They then went on to link their definition to a known sequence in the Online Encyclopedia of Integer Sequences and Voila!, mathematical immortality!

As if the story of three eighth-graders publishing a paper in a college mathematics journal isn’t cool enough, the students collaborated entirely via the internet:  one lives in Washington State, one in Alberta, Canada, and one in Indonesia!

A truly inspiring and remarkable story, and an object lesson in encouraging students to pursue their “wrong” answers!

Math Photo: (Sine) Waves on the Beach

While on vacation, I passed some of my time looking for math on the beach, and I saw a sine wave creeping up the shore.

sine wave in nature

I thought I might be looking too hard for something mathematical, thereby seeing things that weren’t really there.  Thankfully, Geogebra is well-equipped to justify my observations.

wave sine wave equation

Or perhaps it’s more accurate to say that Geogebra helps enable my obsessions.

Number Dictionary

numdic 144This is a fun little website that offers information on numbers from 1 to 1000000:

www.numdic.com

For example, I put in one of my favorite numbers, 144, and saw four ways to write 144 as a difference of squares (always a useful little trick)  and five ways to write it as the sum of primes (in case we were trying to verify Goldbach’s conjecture).

I find the Mayan representation of 144 really cool, and the Roman Numeral representation will make this website handy for crossword puzzles!

Follow

Get every new post delivered to your Inbox

Join other followers: