XXIII = 23
FYI
not sure why the OP decided to use Roman numerals but there you go
@val interesting, is there a specific reason for this?
@guinan I have no idea
@guinan Doing some research, it looks like Arabic numerals replaced Roman numerals in science because they were a lot more convenient for the numbers scientists had to deal with.
Centuries are small numbers, so that was not an issue.
@guinan The French Republican calendar (created in the 18th century) uses Roman numerals for years as well, but it was in use for less than two decades, so they never had to deal with large year numbers.
@val thanks for looking into it!
@guinan Thank you for asking the question, I never asked myself why I use Roman numerals almost every days :D
@guinan In French we always use Roman numerals for century numbers.