Extensions of n-Hom Lie algebras

n-Hom Lie algebras are twisted by n-Lie algebras by means of twisting maps. n-Hom Lie algebras have close relationships with statistical mechanics and mathematical physics. The paper main concerns structures and representations of n-Hom Lie algebras. The concept of nρ-cocycle for an n-Hom Lie algebra (G, [, ...,], α) related to a G-module (V, ρ, β) is proposed, and a sufficient condition for the existence of the dual representation of an n-Hom Lie algebra is provided. From a G-module (V, ρ, β) and an nρ-cocycle θ, an n-Hom Lie algebra (Tθ(V),[, ...,]θ, γ) is constructed on the vector space Tθ(V) = G⊕V, which is called the Tθ-extension of an n-Hom Lie algebra (G, [, ...,], α) by the G-module (V, ρ, β).