Let $x, y : \mathbb{N} \to \mathbb{R}$ each be a D4685: Real sequence such that
(i) | \begin{equation} \lim_{N \to \infty} \sum_{n = 0}^N x_n \neq \emptyset \neq \lim_{N \to \infty} \sum_{n = 0}^N y_n \end{equation} |
Then
\begin{equation}
x \leq y
\quad \implies \quad
\sum_{n = 0}^{\infty} x_n \leq \sum_{n = 0}^{\infty} y_n
\end{equation}