palindrome

A palindrome (from the Greek palindromos "running back again") is a word, verse, sentence, or integer that reads the same forward or backward.  For example, "Able was I ere I saw Elba" or 333313333.  Here is a little longer one by Peter Hilton (a code-breaker on the British team that cracked the German Enigma):

Doc, note. I dissent.  A fast never prevents a fatness.  I diet on cod.

Sotades the obscene of Maronea (3rd century BC) is credited with inventing the palindrome.  Though today only eleven lines of his works still remain, he is thought to have recast the entire Illiad as palindromic verse.  Sotades also wrote lines which when read backwards had the opposite meaning, now sometimes called Sotadic verses.  Sotades attacked many with his unrestrained tongue, and eventually was jailed by Ptolemy II.  Sotades eventually escaped, but Ptolemy's admiral Patroclus caught him, sealed him in a leaden chest and tossed him into the sea.

Though palindromic numbers have no significant role in modern mathematics, the survival of the old mysticism so often attached to numbers (perfect numbers, amicable numbers, abundant numbers...) insures the palindromes a secure place in the heart of the amateur numerologists.

See Also: PalindromicPrime, Strobogrammatic, Tetradic

Related pages (outside of this work)

• The Palindromist A Journal For People Who WRITE - and Read - Palindromes

References:

GC1969

H. Gabai and D. Coogan, "On palindromes and palindromic primes," Math. Mag., 42 (1969) 252--254.  MR0253979