A new proof of Stanley’s theorem on the strong Lefschetz property

Abstract

. A standard graded artinian monomial complete intersection algebra A = k [ x 1 , x 2 , . . . , x n ] / ( x a 1 1 , x a 2 2 , . . . , x a n n ), with k a field of characteristic zero, has the strong Lefschetz property due to Stanley in 1980. In this paper, we give a new proof for this result by using only the basic properties of linear algebra. Furthermore, our proof is still true in the case where the characteristic of k is greater than the socle degree of A , namely a 1 + a 2 + · · · + a n − n .