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T. Amdeberhan
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Yet, another numerical variant of the Vandermonde matrix

In my earlier (soft) MO post, an elementary response was given by Ofir Gorodetsky in regard to the determinant of the symbolic counterpart to the numerical matrix $\pmb{M}_n=(i^j-j^i)_{i,j}^{1,n}$$\mathbf{M}_n=(i^j-j^i)_{i,j}^{1,n}$.

I'm now looking at yet another variation. Let $\pmb{A}_n=(i^j-j^j)_{i,j}^{1,n}$$\mathbf{A}_n=(j^j-i^j)_{i,j}^{1,n}$ be an $n\times n$-matrix. Denote the (signed) Stirling numbers of the first kind by $s(n,k)$. For clarity, here are some contrasting examples: $$\pmb{M}_3=\begin{pmatrix} 0&-1&-2 \\ 1&0&-1 \\2&1&0 \end{pmatrix} \qquad \text{and} \qquad \pmb{A}_3=\begin{pmatrix}0&-3&-26 \\1&0&-19 \\ 2&5&0 \end{pmatrix}.$$$$\mathbf{M}_3=\begin{pmatrix} 0&-1&-2 \\ 1&0&-1 \\2&1&0 \end{pmatrix} \qquad \text{and} \qquad \mathbf{A}_3=\begin{pmatrix}0&3&26 \\-1&0&19 \\ -2&-5&0 \end{pmatrix}.$$ I would like to ask:

QUESTION. Is this true? With the convention that $0^0=1$, we have $$\det\pmb{A}_n=(-1)^n\prod_{j=1}^{n-1}j!\cdot\sum_{k=0}^n\,s(n+1,k+1)\cdot k^k.$$$$\det\mathbf{A}_n=\prod_{j=1}^{n-1}j!\cdot\sum_{k=0}^n\,s(n+1,k+1)\cdot k^k.$$

Remark. If it helps, since the factor $\prod_{j=1}^{n-1}j!$ is exactly the determinant of the Vandermonde matrix, $\pmb{V}_n=(i^{j-1})_{i,j}^{1,n}$$\mathbf{V}_n=(i^{j-1})_{i,j}^{1,n}$, we can say $$\frac{\det\pmb{A}_n}{\det \pmb{V}_n}=(-1)^n\sum_{k=0}^n\,s(n+1,k+1)\cdot k^k.$$$$\frac{\det\mathbf{A}_n}{\det \mathbf{V}_n}=\sum_{k=0}^n\,s(n+1,k+1)\cdot k^k.$$ This formalism goes in the "spirit" of the (specialization) $s_{\lambda}(1,\cdots,1)$ of the Schur polynomials.

Yet another numerical variant of the Vandermonde matrix

In my earlier (soft) MO post, an elementary response was given by Ofir Gorodetsky in regard to the determinant of the symbolic counterpart to the numerical matrix $\pmb{M}_n=(i^j-j^i)_{i,j}^{1,n}$.

I'm now looking at yet another variation. Let $\pmb{A}_n=(i^j-j^j)_{i,j}^{1,n}$ be an $n\times n$-matrix. Denote the (signed) Stirling numbers of the first kind by $s(n,k)$. For clarity, here are some contrasting examples: $$\pmb{M}_3=\begin{pmatrix} 0&-1&-2 \\ 1&0&-1 \\2&1&0 \end{pmatrix} \qquad \text{and} \qquad \pmb{A}_3=\begin{pmatrix}0&-3&-26 \\1&0&-19 \\ 2&5&0 \end{pmatrix}.$$ I would like to ask:

QUESTION. Is this true? With the convention that $0^0=1$, we have $$\det\pmb{A}_n=(-1)^n\prod_{j=1}^{n-1}j!\cdot\sum_{k=0}^n\,s(n+1,k+1)\cdot k^k.$$

Remark. If it helps, since the factor $\prod_{j=1}^{n-1}j!$ is exactly the determinant of the Vandermonde matrix, $\pmb{V}_n=(i^{j-1})_{i,j}^{1,n}$, we can say $$\frac{\det\pmb{A}_n}{\det \pmb{V}_n}=(-1)^n\sum_{k=0}^n\,s(n+1,k+1)\cdot k^k.$$ This formalism goes in the "spirit" of the (specialization) $s_{\lambda}(1,\cdots,1)$ of the Schur polynomials.

Yet, another numerical variant of the Vandermonde matrix

In my earlier (soft) MO post, an elementary response was given by Ofir Gorodetsky in regard to the determinant of the symbolic counterpart to the numerical matrix $\mathbf{M}_n=(i^j-j^i)_{i,j}^{1,n}$.

I'm now looking at yet another variation. Let $\mathbf{A}_n=(j^j-i^j)_{i,j}^{1,n}$ be an $n\times n$-matrix. Denote the (signed) Stirling numbers of the first kind by $s(n,k)$. For clarity, here are some contrasting examples: $$\mathbf{M}_3=\begin{pmatrix} 0&-1&-2 \\ 1&0&-1 \\2&1&0 \end{pmatrix} \qquad \text{and} \qquad \mathbf{A}_3=\begin{pmatrix}0&3&26 \\-1&0&19 \\ -2&-5&0 \end{pmatrix}.$$ I would like to ask:

QUESTION. Is this true? With the convention that $0^0=1$, we have $$\det\mathbf{A}_n=\prod_{j=1}^{n-1}j!\cdot\sum_{k=0}^n\,s(n+1,k+1)\cdot k^k.$$

Remark. If it helps, since the factor $\prod_{j=1}^{n-1}j!$ is exactly the determinant of the Vandermonde matrix, $\mathbf{V}_n=(i^{j-1})_{i,j}^{1,n}$, we can say $$\frac{\det\mathbf{A}_n}{\det \mathbf{V}_n}=\sum_{k=0}^n\,s(n+1,k+1)\cdot k^k.$$ This formalism goes in the "spirit" of the (specialization) $s_{\lambda}(1,\cdots,1)$ of the Schur polynomials.

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LSpice
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Yet, another numerical variant of the Vandermonde matrix

In my earlier (soft) MO post, an elementary responseresponse was given by Ofir Gorodetsky in regard to the determinant of the symbolic counterpart to the numerical matrix $\pmb{M}_n=(i^j-j^i)_{i,j}^{1,n}$.

I'm now looking at yet another variation. Let $\pmb{A}_n=(i^j-j^j)_{i,j}^{1,n}$ be an $n\times n$-matrix. Denote the (signed) Stirling numbers of the first kind by $s(n,k)$. For clarity, here are some contrasting examples: $$\pmb{M}_3=\begin{pmatrix} 0&-1&-2 \\ 1&0&-1 \\2&1&0 \end{pmatrix} \qquad \text{and} \qquad \pmb{A}_3=\begin{pmatrix}0&-3&-26 \\1&0&-19 \\ 2&5&0 \end{pmatrix}.$$ I would like to ask:

QUESTION. Is this true? With the convention that $0^0=1$, we have $$\det\pmb{A}_n=(-1)^n\prod_{j=1}^{n-1}j!\cdot\sum_{k=0}^n\,s(n+1,k+1)\cdot k^k.$$

Remark. If it helps, since the factor $\prod_{j=1}^{n-1}j!$ is exactly the determinant of the Vandermonde matrix, $\pmb{V}_n=(i^{j-1})_{i,j}^{1,n}$, we can say $$\frac{\det\pmb{A}_n}{\det \pmb{V}_n}=(-1)^n\sum_{k=0}^n\,s(n+1,k+1)\cdot k^k.$$ This formalism goes in the "spirit" of the (specialization) $s_{\lambda}(1,\cdots,1)$ of the Schur polynomials.

Yet, another numerical variant of the Vandermonde matrix

In my earlier (soft) MO post, an elementary response was given by Ofir Gorodetsky in regard to the determinant of the symbolic counterpart to the numerical matrix $\pmb{M}_n=(i^j-j^i)_{i,j}^{1,n}$.

I'm now looking at yet another variation. Let $\pmb{A}_n=(i^j-j^j)_{i,j}^{1,n}$ be an $n\times n$-matrix. Denote the (signed) Stirling numbers of the first kind by $s(n,k)$. For clarity, here are some contrasting examples: $$\pmb{M}_3=\begin{pmatrix} 0&-1&-2 \\ 1&0&-1 \\2&1&0 \end{pmatrix} \qquad \text{and} \qquad \pmb{A}_3=\begin{pmatrix}0&-3&-26 \\1&0&-19 \\ 2&5&0 \end{pmatrix}.$$ I would like to ask:

QUESTION. Is this true? With the convention that $0^0=1$, we have $$\det\pmb{A}_n=(-1)^n\prod_{j=1}^{n-1}j!\cdot\sum_{k=0}^n\,s(n+1,k+1)\cdot k^k.$$

Remark. If it helps, since the factor $\prod_{j=1}^{n-1}j!$ is exactly the determinant of the Vandermonde matrix, $\pmb{V}_n=(i^{j-1})_{i,j}^{1,n}$, we can say $$\frac{\det\pmb{A}_n}{\det \pmb{V}_n}=(-1)^n\sum_{k=0}^n\,s(n+1,k+1)\cdot k^k.$$ This formalism goes in the "spirit" of the (specialization) $s_{\lambda}(1,\cdots,1)$ of the Schur polynomials.

Yet another numerical variant of the Vandermonde matrix

In my earlier (soft) MO post, an elementary response was given by Ofir Gorodetsky in regard to the determinant of the symbolic counterpart to the numerical matrix $\pmb{M}_n=(i^j-j^i)_{i,j}^{1,n}$.

I'm now looking at yet another variation. Let $\pmb{A}_n=(i^j-j^j)_{i,j}^{1,n}$ be an $n\times n$-matrix. Denote the (signed) Stirling numbers of the first kind by $s(n,k)$. For clarity, here are some contrasting examples: $$\pmb{M}_3=\begin{pmatrix} 0&-1&-2 \\ 1&0&-1 \\2&1&0 \end{pmatrix} \qquad \text{and} \qquad \pmb{A}_3=\begin{pmatrix}0&-3&-26 \\1&0&-19 \\ 2&5&0 \end{pmatrix}.$$ I would like to ask:

QUESTION. Is this true? With the convention that $0^0=1$, we have $$\det\pmb{A}_n=(-1)^n\prod_{j=1}^{n-1}j!\cdot\sum_{k=0}^n\,s(n+1,k+1)\cdot k^k.$$

Remark. If it helps, since the factor $\prod_{j=1}^{n-1}j!$ is exactly the determinant of the Vandermonde matrix, $\pmb{V}_n=(i^{j-1})_{i,j}^{1,n}$, we can say $$\frac{\det\pmb{A}_n}{\det \pmb{V}_n}=(-1)^n\sum_{k=0}^n\,s(n+1,k+1)\cdot k^k.$$ This formalism goes in the "spirit" of the (specialization) $s_{\lambda}(1,\cdots,1)$ of the Schur polynomials.

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T. Amdeberhan
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In my earlier (soft) MO post, an elementary response was given by Ofir Gorodetsky in regard to the determinant of the symbolic counterpart to the numerical matrix $\pmb{M}_n=(i^j-j^i)_{i,j}^{1,n}$.

I'm now looking at yet another variation. Let $\pmb{A}_n=(i^j-j^j)_{i,j}^{1,n}$ be an $n\times n$-matrix. Denote the (signed) Stirling numbers of the first kind by $s(n,k)$. For clarity, here are some contrasting examples: $$\pmb{M}_3=\begin{pmatrix} 0&-1&-2 \\ 1&0&-1 \\2&1&0 \end{pmatrix} \qquad \text{and} \qquad \pmb{A}_3=\begin{pmatrix}0&-3&-26 \\1&0&-19 \\ 2&5&0 \end{pmatrix}.$$ I would like to ask:

QUESTION. Is this true? With the convention that $0^0=1$, we have $$\det\pmb{A}_n=(-1)^n\prod_{j=1}^{n-1}j!\cdot\sum_{k=0}^n\,s(n+1,k+1)\cdot k^k.$$

Remark. If it helps, since the factor $\prod_{j=1}^{n-1}j!$ is exactly the determinant of the Vandermonde matrix, $\pmb{V}_n=(i^{j-1})_{i,j}^{1,n}$, we can say $$\frac{\det\pmb{A}_n}{\det \pmb{V}_n}=(-1)^n\sum_{k=0}^n\,s(n+1,k+1)\cdot k^k.$$ This formalism goes in the "spirit" of the (specialization) $s_{\lambda}(1,\cdots,1)$ of the Schur polynomials.

In my earlier (soft) MO post, an elementary response was given by Ofir Gorodetsky in regard to the determinant of the symbolic counterpart to the numerical matrix $\pmb{M}_n=(i^j-j^i)_{i,j}^{1,n}$.

I'm now looking at yet another variation. Let $\pmb{A}_n=(i^j-j^j)_{i,j}^{1,n}$ be an $n\times n$-matrix. Denote the (signed) Stirling numbers of the first kind by $s(n,k)$. For clarity, here are some contrasting examples: $$\pmb{M}_3=\begin{pmatrix} 0&-1&-2 \\ 1&0&-1 \\2&1&0 \end{pmatrix} \qquad \text{and} \qquad \pmb{A}_3=\begin{pmatrix}0&-3&-26 \\1&0&-19 \\ 2&5&0 \end{pmatrix}.$$ I would like to ask:

QUESTION. Is this true? With the convention that $0^0=1$, we have $$\det\pmb{A}_n=(-1)^n\prod_{j=1}^{n-1}j!\cdot\sum_{k=0}^n\,s(n+1,k+1)\cdot k^k.$$

In my earlier (soft) MO post, an elementary response was given by Ofir Gorodetsky in regard to the determinant of the symbolic counterpart to the numerical matrix $\pmb{M}_n=(i^j-j^i)_{i,j}^{1,n}$.

I'm now looking at yet another variation. Let $\pmb{A}_n=(i^j-j^j)_{i,j}^{1,n}$ be an $n\times n$-matrix. Denote the (signed) Stirling numbers of the first kind by $s(n,k)$. For clarity, here are some contrasting examples: $$\pmb{M}_3=\begin{pmatrix} 0&-1&-2 \\ 1&0&-1 \\2&1&0 \end{pmatrix} \qquad \text{and} \qquad \pmb{A}_3=\begin{pmatrix}0&-3&-26 \\1&0&-19 \\ 2&5&0 \end{pmatrix}.$$ I would like to ask:

QUESTION. Is this true? With the convention that $0^0=1$, we have $$\det\pmb{A}_n=(-1)^n\prod_{j=1}^{n-1}j!\cdot\sum_{k=0}^n\,s(n+1,k+1)\cdot k^k.$$

Remark. If it helps, since the factor $\prod_{j=1}^{n-1}j!$ is exactly the determinant of the Vandermonde matrix, $\pmb{V}_n=(i^{j-1})_{i,j}^{1,n}$, we can say $$\frac{\det\pmb{A}_n}{\det \pmb{V}_n}=(-1)^n\sum_{k=0}^n\,s(n+1,k+1)\cdot k^k.$$ This formalism goes in the "spirit" of the (specialization) $s_{\lambda}(1,\cdots,1)$ of the Schur polynomials.

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