Appell sequence

Etymology
Named after.

Noun

 * 1)  Any polynomial sequence $$\{p_n(x)\}_{n=0,1,2,\ldots}$$ satisfying the identity $$\frac{d}{dx} p_n(x) = np_{n-1}(x),$$ and in which $$p_0(x)$$ is a non-zero constant.