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# Monthly Archives: March 2007

## Happy pi day!

Happy day! Today, March 14, is celebrated as day, since when today’s date is written in American format (3/14) it corresponds with a common approximation of (3.14). (I don’t know when Europeans celebrate day. [Edit: According to Jester (see below), … Continue reading

Posted in famous numbers
6 Comments

## The Binomial Theorem

The Binomial Theorem is an extremely important and general (and totally sweet) result in the field of combinatorics (which is the branch of mathematics about counting things). Without further ado, here it is: Wait! Don’t let all the fancy symbols … Continue reading

Posted in counting, pascal's triangle, pattern
2 Comments

## Challenge #9 Solution

In Which Our Hero (You) Discovers Several Methods of Proving a Combinatorial Identity Involving Pascal’s Triangle (Read Challenge #9 first if you haven’t already…)

Posted in counting, pascal's triangle, proof, solutions
4 Comments