Pascal’s Triangle is a special triangular arrangement of numbers
used in many areas of mathematics. It is named after the famous
17th century French mathematician Blaise Pascal because he
developed so many of the triangle’s properties. However, this
triangular arrangement of numbers was known by the Arabian poet
and mathematician Omar Khayyam (c 1044-1123) and the Chinese
mathematician Zhu Shijie (c 1260-1320) some 250 years before
Pascal. At the top of the triangle is a 1, which makes up the
0th row. The 1st row (1, 1) contains two 1s each formed by
adding the two numbers above them, one to the left and one to
the right, in this case 0 and 1. (All numbers outside the
triangle are 0s.) Do the same to create the 2nd row; 0 + 1 = 1,
1 + 1 = 2, 1 + 0 = 1 and all subsequent rows. A number in the
triangle can be found by using nCr (n choose r), where n is the
number of the row and r is the number of the element in that
row. This is especially helpful to find a particular term in the
expansion of a binomial in the