I can't work out a single letter to get a start.The first word is --RI-- and the numbers of the first two letters are 15 and 2 and the last two are 11 and 23. Any ideas?
Sorry, the numbers for RI are 6 and 16. Another word is - 6 16 - - -, in other words -RI---. The number of the letter after 16 is 15 which is also the first letter of the other word I am looking for.