This is a variation of Elite Etile.

Consider all possible valid English words having at least 3 letters and at most 13 letters that satisfy the following conditions:

• Each word ends with a letter that immediately follows the letter that the word begins with. (For example, if a word begins with c it must end in d), and:
  
• Reversing the letters we obtain another valid English word, and:
• None of the words can be proper nouns, acronyms or abbreviations, and:
• None of the words can be hyphenated like A-bomb, X-ray etc.

What is the longest word that satisfies all the given conditions? What are the respective first word and the last word appearing alphabetically? Does there exist any valid English word having more than 13 letters that satisfies all the conditions?

(In reply to The two letter word(s?) by Jer)

As a condition of the problem is to "Consider all possible valid English words having at least 3 letters..." , the 2-letter words are not valid. If the condition did allow them, then there would be an additional five word pairs to list:

• ab - (informal) abdominal muscle
  ba - (Egyptian myth) the soul of a person or god
• de - of; from 
  ed - (informal) education
• no - negative reply
  on - in operation or operational; supported by the top surface of something
• op - (informal): operation; telephone or radio operator
  po - (British informal) chamber pot
• tu - a traditional Chinese unit of distance equal to 250 li
  ut - the syllable naming the first (tonic) note of any major scale in solmization

Posted by Dej Mar on 2012-04-27 17:02:46