What is the Pascal's Triangle?

Answer 1

Pascal's triangle is an abstract arrangement of numbers which looks like this:

1

1 1

1 2 1

1 3 3 1

1 4 6 4 1

1 5 10 10 5 1

... [continued ad infinitum] ...

Each number is equal to the sum of two numbers, the numbers just above it to the left and the number just above it to the right. (if either the number to the right or to the left is missing, it is assumed to be 0)

the formula is (r-1)!/[(c-1)!*(r-c)!]. You might want to check out the related link below.