Most mariners can tell you the significance of a ship’s IMO number but few know how the number is chosen. One of the guys mathematicians over at k… Click HERE to read the full blog article.
It might be worth noting that the introduction of the IMO-number was in 1987 through adoption of resolution A.600(15).
And it became mandatory from 1994 onwards for passengerships > 100 GT & cargoships >300 GT.
More info here on the IMO-page:
http://www.imo.org/Facilitation/mainframe.asp?topic_id=388