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OK but I knew all these things already.
Here is a slight but useful modification. In D5 instead of the instruction
above put '=d$1*d4+c4', and copy that into a huge rectangle. The dollar sign,
$, will cause the index that follows it to remain constant. Thus when you copy
this into other rows and columns, d$1 will be the element of that column in the
first row.
When you again put 1 in c4 you get numbers called "The Stirling numbers
of the second kind". Binomial coefficients count the number of subsets
of an n element set having k elements in them. The Stirling number here counts
the number of partitions of a set of n elements into k disjoint blocks.
Exercises:
0.6 Set this up on your own machine. Solution
0.7 Binomial coefficients count the number of subsets of an n element set
having k elements in them. The Stirling number here counts the number of partitions
of a set of n elements into k disjoint blocks. Prove these two statements. Solution
0.8 Invent a good question for this spot.
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