Errand Chronicle 31011 · Entry #7

Pyresh's Formula VII

Objective
Found a trace of Pyresh. Let's solve Pyresh's Formula written on it.
Solve the secret formula left behind by Pyresh and type it in the chat window;
Dialogue
Trace of Pyresh Dialogue
Pyresh left behind a piece of his realizations.
Numbers are written in what looks to be a riddle of sorts.
After a sequence of numbers follows a question mark.
It's as if someone wanted their formula to be solved by another.
77, 63, 27, 23 ...
Find the number that comes next.
Trace of Pyresh Dialogue (Alt)
77, 63, 27, 23 ...
Find the number that comes next.
Trace of Pyresh Completion
The answer of this was to separate the numbers by their digits, then multiply the two digits,
add the two digits, and finally add the two values, which results in the next number.
Now you're starting to feel the mental fatigue kick in.
What kind of thoughts possessed Pyresh's daily life?
Other Errands in This Chronicle

9 further errands share this chronicle — the same travelers, the same stretch of road.

Details
Chronicle31011
Entry7
Quest Giver
Turn-in
Summary
The answer of this was to separate the numbers by their digits, then multiply the two digits,
add the two digits, and finally add the two values, which results in the next number.
Now you're starting to feel the mental fatigue kick in.
What kind of thoughts possessed Pyresh's daily life?