An example of a simple derivation in two variables
An example of a simple derivation in two variables
Let $k$ be a field of characteristic zero. We prove that the derivation $D=\partial /\partial x+(y^s+px)(\partial /\partial y)$, where $s\geq 2$, $0\not =p\in k$, of the polynomial ring $k[x,y]$ is simple.