T is said to have nice property if either 𝒜′ (T) or 𝒜′ (T*) is a commutative strictly cyclic operator algebra. This paper uses the multiplication operators on Sobolev space to construct a class of ...

For 𝑎, 𝑏 ∈ ℂ, the Lie algebra 𝒲 (𝑎, 𝑏) is the semidirect product of the Witt algebra and a module of the intermediate series. In this paper, all biderivations of 𝒲 (𝑎, 𝑏) are determined.