Why is this injection from $\mathbb{N^N}$ to $\mathbb{N}$ wrong?
47653
Cantor diagonalization and fundamental theorem
14161
Proof of when is $A=X^TX$ invertible?
93031
How to show that $\mathbb{Z}$ with the operation $m*n=m+(-1)^m n$ is associative?
79056
Prove that $\mathbb Z^n$ is not isomorphic to $\mathbb Z^m$ for $m\neq n$
42883
Cross product in $\mathbb R^n$
723
Is there a constructive way to exhibit a basis for $\mathbb{R}^\mathbb{N}$?
110569
Does anyone know a closed-form expression for a bijection between $\mathbb{N}^k$ and $\mathbb{N}$?
20437
Closed surjection that does not preserve regularity
121198
$W^{1,1}(\mathbb{R}^n)$ is not compactly embedded in $L^1(\mathbb{R}^n)$?
109710
Bijection between $\mathbb N \times \mathbb N$ and $\mathbb N$
105014
Is the zero vector in $\mathbb{R}^n$ by itself a subspace of $\mathbb{R}^n$?
24072
Intuitive explanation of why $\dim\operatorname{Im} T + \dim\operatorname{Ker} T = \dim V$
75373
Show that $2^n>n$ for $n\in \mathbb{N}$
78075
Why can I apply $HS^\dagger$ and then measure in the computational basis to measure $Y$?
141991
What does the notation $S^n$ mean?
117793
Finding a function $\mathbb{N} \to \mathbb{N}$ that is surjective but not injective.
86015
$\mathbb Q[x]/(x^2+1)$ is not isomorphic to $\mathbb Q[x]/(x^2+2)$