What is the most used way to write for-loop as pseudocode?
Just use whatever is clearest in your particular situation. Pseudocode is not a formal language with formal syntax.

Note that for $e\in [1,8]$ do doesn't necessarily imply that the values $1$, $2$, ..., $8$ are assigned in any particular order.  Note that $\{x\in \mathbb{N}\mid 1\leq x\leq 8\}$ is somewhat redundant: an algorithm can't possibly loop over all the reals or rationals between $1$ and&nbsp;$8$, so the set can only really be a set of natural numbers. Finally, note that the association $\mathrm{e}=2.71828\ldots$ is very strong, so $e$&nbsp;is often a poor choice of variable name.