Find the number n such that the following alphanumeric equation:

KYOTO
KYOTO
__+ KYOTO__
TOKYO

has a solution in the base-n number system.

*(Each letter in the equation denotes a digit in this system, and different letters denote different digits)*
(In reply to

'The Interested Reader' by Charley)

I have since independently verified that the value of n ( the base is 9); and there are precisely four solutions

KYOTO = 13040, 16050, 23070, 26080.

Yes, truly a great puzzle.