A D997: Natural number sequence $F : \mathbb{N} \to \mathbb{N}$ is the Fibonacci natural number sequence if and only if

(1)	$F_0 = 0$
(2)	$F_1 = 1$
(3)	$\forall \, n \geq 2 : F_n = F_{n - 1} + F_{n - 2}$

Let $F : \mathbb{N} \to \mathbb{N}$ be a D997: Natural number sequence such that

(i)	$F_0 = 0$
(ii)	$F_1 = 1$

Then $F$ is the Fibonacci natural number sequence if and only if \begin{equation} F_2 = F_1 + F_0, \quad F_3 = F_2 + F_1, \quad F_4 = F_3 + F_2, \quad \dots \end{equation}