Guichard-Combinatorics-Graph-Theory · Problem 3.2.2

Generating Functions

Mathematics — Probability · exponential-generating-functions

Problem

Find an exponential generating function for the number of permutations with repetition of length

n

of the set

\{a, b, c\}

, in which there are an odd number of

a

s, an even number of

b

s, and an even number of

c