Matrices that commute with all matrices
4280
A linear operator commuting with all such operators is a scalar multiple of the identity.
85193
direct product commutes with tensor product?
43570
Finding two non-zero matrices where $AX = BA$
17421
Linear Algebra: Find a matrix A such that T(x) is Ax for each x
20659
Is trace invariant under cyclic permutation with rectangular matrices?
120744
How many $n\times m$ binary matrices are there, up to row and column permutations?
10014
Is there a built-in procedure for simultaneous diagonalization of a set of commuting matrices?
136389
Finding an isomorphic subring of matrices
55230
Dimension of set of commutable matrices
136329
A matrix is similar to its transpose
12955
Classification of $n\times n$ real matrices up to congruence
6659
Approximating commuting matrices by commuting diagonalizable matrices
123410
Find dimension of Commuting matrices over field of prime elements
25357
Matrices $B$ that commute with every matrix commuting with $A$
96822
Array of Matrices in MATLAB
36613
Prove that simultaneously diagonalizable matrices commute
123726
$2\times 2 $ matrices over $\mathbb{C}$ that satisfy $\mathrm A^3=\mathrm A$