2 problems

Let $\mathbf{w} \in \mathbb R^{n \circ l}$ be an even-order symmetric real tensor, and let $\lambda_k^v(\mathbf{w})$ denote its $k$th variational eigenvalue, defined by … where $S$…

Let $\mathcal B$ be a nonnegative fourth-order PS-tensor, and let the upper bound in Theorem denote the bound established there for its M-spectral radius $\rho_M(\mathcal B)$. Tigh…