Question: a. How many onto functions are there from a set with three elements to a set with two elements?
b. How many onto functions are there from a set with three elements to a set with five elements?
c. How many onto functions are there from a set with three elements to a set with three elements?
d. How many onto functions are there from a set with four elements to a set with two elements?
e. How many onto functions are there from a set with four elements to a set with three elements?
f. Let cm,n be the number of onto functions from a set of m elements to a set of n elements, where m ≥ n ≥ 1. Find a formula relating cm,n to cm-1,n and cm-1,n-1.