Upper bounds on the dimension of the Schur $\mathsf{Lie}$-multiplier of $\mathsf{Lie}$-nilpotent Leibniz $n$-algebras

Abstract

The Schur $\mathsf{Lie}$-multiplier of Leibniz algebras is the Schur multiplier of Leibniz algebras defined relative to the Liezation functor. In this paper, we study upper bounds for the dimension of the Schur $\mathsf{Lie}$-multiplier of $\mathsf{Lie}$-filiform Leibniz $n$-algebras and the Schur $\mathsf{Lie}$-multiplier of its $\mathsf{Lie}$-central factor. The upper bound obtained is associated to both the sequences of central binomial coefficients and the sum of the numbers located in the rhombus part of Pascal's triangle. Also, the pattern of counting the number of $\mathsf{Lie}$-brackets of a particular Leibniz $n$-algebra leads us to a new property of Pascal's triangle. Moreover, we discuss some results which improve the existing upper bound published in [23] for $m$-dimensional $\mathsf{Lie}$-nilpotent Leibniz $n$-algebras with $d$-dimensional $\mathsf{Lie}$-commutator. In particular, it is shown that if $\mathfrak{q}$ is an $m$-dimensional $\mathsf{Lie}$-nilpotent Leibniz $2$-algebra with one-dimensional $\mathsf{Lie}$-commutator, then $\dim\mathcal{M}_{\mathsf{Lie}}(\mathfrak{q})\leq \frac{1}{2}m(m-1)-1.$