I have solved it
This is a great problem. I was totally excited when I found the answer. Of course, the excitement starts immediately when you figure out how can you ever get as huge numbers as 10850 or 2616 in the sequence. ;-)
You will need more then ten keystrokes to write down the correct answer, and once you know the explanation, you will be absolutely sure that it is the correct answer.
You also need to know how to use the internet and how to calculate x^2 for x integers smaller than 10. No more hints. If someone can't live without an answer, he can try to ask me at
[email protected]