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Asymptotic spectral properties of the Hilbert $L$-matrix

We study asymptotic spectral properties of the generalized Hilbert $L$-matrix \[ L_{n}(ν)=\left(\frac{1}{\max(i,j)+ν}\right)_{i,j=0}^{n-1}, \] for large order $n$. First, for general $ν\neq0,-1,-2,\dots$, we deduce the asymptotic distribution of eigenvalues of $L_{n}(ν)$ outside the origin. Second, for $ν>0$, asymptotic formulas for small eigenvalues of $L_{n}(ν)$ are derived. Third, in the classical case $ν=1$, we also prove asymptotic formulas for large eigenvalues of $L_{n}\equiv L_{n}(1)$. I particular, we obtain an asymptotic expansion of $\|L_{n}\|$ improving Wilf's formula for the best constant in truncated Hardy's inequality.