Number of distinct surjective functions
61
Calculating the total number of surjective functions
152946
how many distinct values does it have?
37012
The number of summands $\phi(n)$
158381
Distinct balls into distinct boxes
74453
Injective and Surjective Functions
24212
proving how many permutations exist.
104898
Proper notation for distinct sets
117793
Finding a function $\mathbb{N} \to \mathbb{N}$ that is surjective but not injective.
105886
A question on the proof of 14 distinct sets can be formed by complementation and closure
45792
Rigorous proof that surjectivity implies injectivity for finite sets
103769
The Cartesian product of a finite number of countable sets is countable
26343
Number of certain (0,1)-matrices, Stanley's Enumerative Combinatorics
108691
Characterize the natural numbers $n$ such that there is a surjective group homomorphism from $S_n$ to $S_{n-1}$.
117502
Proving that a certain continuous function is surjective.
7938
Number of Homomorphisms from $\Bbb{Z}_m$ to $\Bbb{Z}_n$
137621
The Number of Topologies on a Finite Set
136842
$|x-f(x)|<5777$, Show that $f$ is surjective