Pascal's Triangle: A Wonder Of Mathmetics
- Elon譯閬 Tsay蔡
- Aug 26
- 2 min read
Pascal's triangle is a wonderful element of math. It can help us solve numerous math problems! Pascal's triangle consists of "rows" and "diagonals". Let me show you what this means: diagonal 1: 1-1-1....
row 0 1. diagonal 2 1-2-3....
row 1 1 1 diagonal 3 1-3-6...
row 2 1 2 1 diagonal 4: 1-4...
row 3 1 3 3 1 and so on..
row 4 1 4 6. 4 1
Do you notice anything?the triangle begins with 1 1-1, and keeps adding ones on the left and right sides, and for the ones that aren't on that side, that is the sum of the 2 numbers above it!
Here is a formula for the nth number in diagonals 1,2,3 and 4:
diagonal 1: all 1's
diagonal 2: n, because these are the counting numbers.
diagonal 3: These are the triangle numbers, let me quickly show you how to calculate the nth triangle number,
Say n=2. We have the 2rd triangle number, which is 1+2. We can represent this with a triangle:
x
xx
(x=1 dot)
If we copy the triangle and make it so that the diagonals align, we get this:
xyy
xxy
We get a rectangle!
we have one side with length 2, and one with 2+1, so the area is 2(2+1)! But we used 2 triangles so we get
2(2+1)/2! Because we had our 2nd triangle number, we get 3. But what if we had, say, the 10th?
We could replace 2 with 10! 10+1=11, 11*10/2=55!
Diagonal 4: This is a bit more complex but we can get the nth number of the diagonal by using the formula n choose 3 (n!/(3!*(n-3)!).
General Formula:
The mth number on the nth diagonal will be m choose n-1 (m!/((n-1)!*(m-n+1)!) (BTW anything choose 0=1)
That'll be it for now! Thanks for reading!

hi elon