The central closure of the simple “strange” Lie superalgebras extended over a commutative algebra

In this work we study central extensions of Lie superalgebras $g(A)$, where $g=P(n-1)$ are simple Lie superalgebras from one of the so-called “strange” series. We show that universal central extensions of these Lie superalgebras ara trivial, i.e., they are isomorphic to the superalgebras $g(A)$.