Let F=X-H:$k^n$ → $k^n$ be a polynomial map with H homogeneous of degree 3 and nilpotent Jacobian matrix J(H). Let G=(G1,...,Gn) be the formal inverse of F. Bass, Connell and Wright proved in [1] that the homogeneous component of $G_i$ of degree 2d+1 can be expressed as $G_i^{\left(d\right)}={\sum }_T\alpha {\left(T\right)}^{-1}{\sigma }_i\left(T\right)$, where T varies over rooted trees with d vertices, α(T)=CardAut(T) and ${\sigma }_i\left(T\right)$ is a polynomial defined by (1) below. The Jacobian Conjecture states that, in our situation, $F$ is an automorphism or, equivalently, $G_i^{\left(d\right)}$ is zero for sufficiently large d....