On some 4-by-4 matrices with bi-elliptical numerical ranges
نویسندگان
چکیده
منابع مشابه
Some results on higher numerical ranges and radii of quaternion matrices
Let $n$ and $k$ be two positive integers, $kleq n$ and $A$ be an $n$-square quaternion matrix. In this paper, some results on the $k-$numerical range of $A$ are investigated. Moreover, the notions of $k$-numerical radius, right $k$-spectral radius and $k$-norm of $A$ are introduced, and some of their algebraic properties are studied.
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ژورنال
عنوان ژورنال: Linear and Multilinear Algebra
سال: 2020
ISSN: 0308-1087,1563-5139
DOI: 10.1080/03081087.2020.1857326