User blog comment:Primussupremus/Supremus array notation/@comment-25337554-20170326010203

Wait. Give me an exact definition.

Is "5→6 → 7 → 8 → 9" one item or the chain of length five?

And, which is  5→6 → 7 → 8 → 9, the number of arrows or the number of " 5→6 → 7 → 8 → 9 " itself? (These two numbers are different by one)