You have an inequality symbol missing at the end of the quote (between i and j). That made it slightly difficult for me to parse it on my first read-through ("Why does it say 'for all i, j' when the only index in the expression is 'i'?").
I don't know if you know, but just in case you (or someone else) don't: There is no inequality symbol on the computer keyboard, so he used a typical programmer's inequality symbol which is "!=". So yes, it is not easily readable (i! is a bad combination...) but totally correct.
Here's the new thread for posting quotes, with the usual rules: