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Statistics of spectral properties of matrix-valued random variables.

7 votes
Accepted

Is this combinatorial identity known? (of interest for random matrix theory)

Firstly, exploit the finite support to simplify the limits of the sums. Secondly, split the second sum. We get $$\begin{align*}A(r,b) =& \sum\limits_{m=1}^{r} (2m-1) {r \choose b-m}{r \choose b+m-1} \ …
Peter Taylor's user avatar
  • 7,226
5 votes

Matrices over $\mathbb{F}_p$ that have nonzero determinant under any element permutation

$\det \begin{pmatrix} 1 \end{pmatrix} = 1$ works for any $p$. $\det \begin{pmatrix} 0 & 1 \\ 1 & 1 \end{pmatrix} = -1$ similarly. For $n=3$ we require $p \ge 5$. By exhaustion there's no solution for …
Peter Taylor's user avatar
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