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1 vote
1 answer
205 views

Van der Waerden conjecture and Alexandrov-Fenchel inequality

The Van der Waerden conjecture is a lower estimate of the permanent of a doubly stochastic matrix. In this article in Wikipedia it is stated that Egorychev's proof uses the Alexandrov-Fenchel ...
10 votes
1 answer
268 views

A bound for the permanent of a nonnegative matrix

Suppose $A=(a_{ij})$ is a symmetric (0,1)-matrix with 1's along the diagonal, and let $A_{ij}$ be the matrix obtained by removing the $i$-th row and $j$-th column. Based on substantial numerical ...
4 votes
1 answer
173 views

Subspaces of vanishing permanent

Suppose that $p\ge 5$ is a prime, $n$ a positive integer divisible by $p-1$, and $L<\mathbb F_p^n$ a subspace of dimension $d=n/(p-1)$. Do there exist vectors $l_1,\dotsc,l_n\in L$ such that the ...
2 votes
0 answers
354 views

Spectral norm bound for lower triangular matrix

Let $A$ be a $0/1$ square matrix which can be permuted to a non singular or a singular lower triangular matrix. Determinant is either $0$ or $1$. Can we provide tighter upper bounds on its spectral ...
20 votes
2 answers
1k views

Euler numbers and permanent of matrices

Motivated by Question 402249 of Zhi-Wei Sun, I consider the permanent of matrices $$e(n)=\mathrm{per}\left[\operatorname{sgn} \left(\tan\pi\frac{j+k}n \right)\right]_{1\le j,k\le n-1},$$ where $n$ is ...
0 votes
1 answer
248 views

$\mathbb R$ and $\mathbb F_2$ rank in boolean matrix product

By rank I imply rank over reals ($\mathbb R$). I consider two $n\times n$ matrices $A,B$ having entries in $0/1$. The product below follows usual matrix product rules except $xy$ is $AND(x,y)$ and $x+...
4 votes
0 answers
99 views

Volume interpretation of number of perfect matchings in bipartite planar graphs

Permanent of biadjacency of bipartite graphs is the number of perfect matchings. In the case of planar graphs we can obtain an orientation with sign changes and get away with computing the determinant ...
3 votes
0 answers
75 views

Bunch of matrices with vanishing permanents

$\DeclareMathOperator{\Per}{Per}$ $\newcommand{\oI}{{\overline I}}$ $\newcommand{\oJ}{{\overline J}}$ Is it possible to classify pairs $(A,B)$ of square, nonsingular matrices over a field of prime ...
13 votes
1 answer
311 views

Permanent of the Coxeter matrix of a distributive lattice

Let $L$ be a finite distributive lattice with $n$ elements. Let $C=(c_{x,y})$ be the $n \times n$ matrix with entry 1 in case $x \leq y$ and 0 else. The Coxeter matrix of $L$ is defined as the matrix $...
1 vote
1 answer
698 views

Permanent of a matrix with duplicate rows/columns

I'm trying to find an efficient algorithm/technique to calculate, or approximate, the permanent of a matrix. After reading some literature, it seems nothing exists faster than Ryser's algorithm in the ...
-1 votes
1 answer
383 views

On the permanent dominance conjecture for symmetric group

The Lieb's permanent dominance conjecture states that the expression $$\frac{d_{\chi}^HA}{\chi(e)}\le per(A)$$ holds for all positive semidefinite matrices $A$, where $d_{\chi}^HA=\sum_\limits{\sigma\...
2 votes
0 answers
123 views

Mod $2$ of $\#PM(G)$ for arbitrary G?

Permanent mod $2$ of biadjacency gives polynomial time algorithm of $\#PM(G)\mod 2$ of perfect matchings of bipartite graph. Is there a similar efficient strategy for general graphs?
2 votes
1 answer
118 views

What $n$-linear sums can be extracted from a product of linear polynomials in $m$ variables?

Let $\boldsymbol{c}_1, ..., \boldsymbol{c}_n$ be $n$ orthonormal, $m$-dimensional complex vectors, with $\boldsymbol{c}_i = (c_{i,1}, ..., c_{i,m})$. Consider the following polynomial in $x_1,..., x_m$...
3 votes
0 answers
104 views

Rank relation to maximum subpermanent and subdeterminant?

Given a $\pm1$ matrix $M$ of rank $r$ let the largest subdeterminant be $d$ and let the largest subpermanent be $p$. Are there relations/bounds that connect $r$, $d$ and $p$? Are there geometric and ...
3 votes
1 answer
170 views

Permanent of distorted matrix

Let $J$ be all $1$ matrix. Suppose permanent of $M$ is $p$ and $a\in\Bbb Z$. Is there a closed formula or at least a faster than Ryser's technique to find $Permanent(M+aJ)$?
2 votes
0 answers
364 views

Permanent of a matrix

Let $n \geq 2$ $a,b$ complex numbers (or in some other ring if you wish). What is the permanent of the matrix $$M(a,b,n)= \begin{bmatrix} a & a & a & ... & a & a \\ a &...
1 vote
0 answers
68 views

Zero as a repeated permanental root for a matrix over a finite field

All, Suppose $A \in Mat(n, \mathbb{F}_{q})$ for $q$ prime, $q \geq 5$, and $n \geq 2^{q-2}$ . Let $\pi_A(x)$ be the permanental polynomial for $A$. That is, \begin{equation*} \pi_{A}(x)=per(xI-A). \...
3 votes
0 answers
237 views

Multi-dimensional permanent of structured tensor

I am facing the multidimensional permanent \begin{equation} \text{perm}(W) = \sum_{\sigma, \rho \in S_n} \prod_{j=1}^n W_{j, \sigma_j, \rho_j } \end{equation} of a 3-tensor $W_{j,k,l}$ of ...
4 votes
2 answers
620 views

Is Ryser's conjecture on permanent minimizers still open?

Let $A(k,n)$ be the set of $\{0,1\}$ matrices of order $n$ with all their line sums equal to $k$. Conjecture number 5 on the list from Minc's book, attributed to Ryser, says that if $A(k,n)$ ...
13 votes
2 answers
946 views

Computing a large permanent

Is there a practical way to compute the permanent of a large ($91 \times 91$) $(0,1)$ matrix? I have tried to use the matlab function written by Luke Winslow which works great for smaller matrices ...