While thinking about letters, numbers and palindromes, I realized (am sure many of you also would have) that there are 7 English letters, namely, H, I, N, O, S, X and Z that read the same upside down. It is not difficult to further realize that there are 2 numerals, namely, 0 and 8 that read the same upside down.
I was stressing my brain to find out palindromes made of these letters so that they read the same even upside down and not just left to right or right to left. I could find two words - NOON and SEXES. If you find more, please do post them as comment.
I was stressing my brain to find out palindromes made of these letters so that they read the same even upside down and not just left to right or right to left. I could find two words - NOON and SEXES. If you find more, please do post them as comment.
Fine thought!
ReplyDeleteReminds me of long back when through regexp magic I tried searching longest words that you can type using a single hand, in a single row of the typewriter etc.
If you have a palindrome checker filter program, the following may work on your Linux:
/home/niraj> grep -i "^[HINOSXZ]+$" /usr/dict | palindrome > output.txt
Let us know whether it worked :-)
Thanks, Bhushit.
ReplyDeleteYour command needs a bit of tweaking as even the other characters in the palindrome needs to be one of HINOSXZ for the word to be a universal palindrome (for the lack of better phrase - we can also call them 2D palindromes as they read the same Right to Left or Left to Right or Upside down).
I did not have palindrome utility so wrote one and found only few matches as the following:
NON
SIS
However, strictly speaking, they are NOT words.
Someday, I (or someone of you) may search through entire dictionary to find out all universal words.
Note that we have limited our discussion to capitalized words. Similar exercise could be performed assuming that words are non-capitalized. We could also look at other languages like Gujarati or Hindi! On that, may be, some other day...
What about mirror symmetric palindromes? Those using AHIMOTUVWXY.
ReplyDeleteAlso, the mirror symmetry along the middle - BCDEHIK(?)OS.