Anyone know what the longest combination of three different English words that’s palindromic? Restrictions: the words must not be related to each other and none may individually be a palindrome. However, capitalized words are acceptable.
By googling, I found that the longest two-word combination is probably shallot ayatollahs (17-letters). (There’s other, longer ones, but they violate the restrictions. For example, if you remove the restriction about being individually palindromic, then the answer is probably evitative levitative (19).) Anyone able to better these? And I have no idea about the 3-word answer, so that’s open to the floor.
23 letters. That’s the best so far. I expect there’s longer ones out there, but likely no one’s looked for them. I found one page with all the two-word examples that can be generated from a word list, but not three. The amount of computer time to find them probably goes up exponentially, so perhaps that’s why such a list doesn’t seem to be out there.
I agree with you on senseless 'dromes, but only when one is trying to make a sentence. I’m just looking for any three words, so that’s not an issue here.
It does indeed. I wrote a simple python program to randomly test 3-word pairs (I used the wordlist at this site), and, without doing any optimization, it can test a bit over 320,000 triples a second, so it should finish testing in about 4,000 years. Except it’s picking words at random (since an ordered search is really unlikely to find anything at the beginning), so it is repeating a small amount of work.
I’m gonna let it run for a while and see if it finds anything, but I don’t have high hopes. There are some pretty obvious optimizations I could make, though, like pre-testing which pairs could conceivably be start/end words, so I’ll probably do those if I have time. I bet I can get the expected runtime under 100 years, easy.
I should note that you can construct a long triple by taking the longest reversal pair (stressed/desserts) and inserting the longest single word palindrome (tattarrattat) between them. But that violates the rule against an individual word being a palindrome.
So, I have now running a version that pre-searches for all sets of pairs of words that could be the start/end of a palindrome triple. I’m limiting it to words that are at least 4 letters long.
For example, it recently found “acataposis” and “pataca”.
Those are getting written to a file, and based on progress so far, it’ll be done in a few days. Testing all the words as a middle word will be very quick once I have that list. So, here comes.
I expect that someone could write something even faster given that few days, but we’re now in the range where I’m going to let the machines do the work. I will report back.
Don’t need the apostrophe; these don’t have to make any kind of sense and teragram is a noun. So we may have a winner here with 29 letters (which is actually one more than the one I suggested constructing.) We’ll see if walrus’ program does any better.
The 100,000+ word list I use cannot improve on enalzi’s 29-letter solution. Other 29-letter palindromes include
rednesses: sensuousnesses sender
Dropping the restriction that words be unrelated we have a 35-letter solution
Kinnikinniks’ sensuousness: kinnikinnik
which is more-or-less meaningful: “A small-time Colorado-based mountain music group uses as their sensual indulgence, the Native American smoking mixture after which the band was named.”
My script has completed! It didn’t find any longer than 29 that satisfy all the requirements, although it did find this 29-letter one that I quite like:
“retrovaccinate tetanic cavorter”
It’s actually an on-topic sentence with reasonable meaning (assuming cows can get tetanus?) that requires no punctuation or proper nouns. This is cool!
My script also found a missing newline in the wordlist I was using, since it thinks “redrawerredrawers” is a word, which it is not.
It’s still a palindrome. We ignore spaces and punctuation for them. Any other SDMB palindromic usernames? I seem to remember there was one more (at least) but can’t remember what it was.
