published: May 4, 2021 — last modified: October 23, 2025
Assume, while digging out an ancient site from 450 AD, you found a mysterious stone with a digital display. Your analysis finds five inputs for five segments (a-e) and six outputs (1-6). It seems to be a classic multiplexed display.
What is this display for?
What is the highest continuous sequence of numbers it can display?
You connected the display, and it is still working. Now you can enable and disable the segments.
| 1 | 2 | 3 | 4 | 5 | 6 | |
|---|---|---|---|---|---|---|
| a | ||||||
| b | ||||||
| c | ||||||
| d | ||||||
| e |
This display was made to display Roman numerals.
Sadly, the range of displayed numbers is very limited. Depending how you write the letter V, you can count up to 16 or 17.
If you do not need a continuous sequence, the largest number is MM.
I hope you enjoyed this logic puzzle. Yet, it didn’t contain any logic gates, but who knows how the Romans built it 😉. Let me know if you like to see more puzzles like this.
If you have any questions, missed information, or want to provide feedback, feel free to comment below. 😄
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