CO42 Exponential Generating Functions & Permutations of Multisets

How many n digit numbers can you construct using only the digits 1, 4, and 7 while using an even number of 1's? We introduce exponential generating functions in order to find s-permutations of a multiset with t types of elements where, for each element type, we have some kind of restriction on the number of those type of elements in our permutation.

A series of lectures on introductory Combinatorics. This full course is based on my book
Shahriar Shahriari, An Invitation to Combinatorics, Cambridge University Press, 2022.

For an annotated list of available videos see

This is the sixth lecture in a sequence of lectures on generating functions. It is preceded by

Shahriari is the William Polk Russell Professor of Mathematics at Pomona College in Claremont, CA USA
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