Set up a new sheet with the integers around the edge as before. This time put in d5: '=d4+c4'and copy it into a huge rectangle from d5 to cc100 (say). You should get a huge mass of zeroes. Now set c4 = 1. What do you find?

You should find
"Pascal's Triangle"
or the
binomial coefficients.

Exercise 0.5 Do this and answer the question which is larger, the binomial
coefficient C(15,5) or C(14,6)? Solution