Palindrome

: For the movie, see Palindromes (movie)

fun tel -> lol.pop

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C

Brian Westley made a C program for the 1987 International Obfuscated C Code Contest which is a line-by-line palindrome: http://www.ioccc.org/1987/westley.c

Related Topics:
Brian Westley - International Obfuscated C Code Contest

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The world's longest palindromic sentence

To celebrate 20:02 02/20 2002, a palindromic day, Peter Norvig wrote on that day a computer program that produced the world's longest palindromic sentence: 17,259 words long. http://www.norvig.com/palindrome.html

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For a long palindrome in English that reads easier and attempts to flow is viewable here.

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Symmetry by the words

Some palindromes use words as units rather than letters. They Might Be Giants released a single called I Palindrome I (on the album Apollo 18), the lyrics of which include the word palindrome: "Son I am able," she said, "though you scare me." "Watch," said I, "beloved," I said, "watch me scare you though." Said she, "able am I, Son."

Related Topics:
They Might Be Giants - Apollo 18

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Other examples:

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• You can cage a swallow, can't you, but you can't swallow a cage, can you?
• Fall leaves as soon as leaves fall.
• So patient a nurse to nurse a patient so.

Symmetry by the lines

Still other palindromes take the line as the unit. The poem Doppelganger, composed by James A. Lindon, is such a palindrome.

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Doppelganger

: Entering the lonely house with my wife

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: I saw him for the first time

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: Peering furtively from behind a bush --

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: Blackness that moved,

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: A shape amid the shadows,

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: A momentary glimpse of gleaming eyes

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: Revealed in the ragged moon.

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: A closer look (he seemed to turn) might have

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: Put him to flight forever --

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: I dared not

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: (For reasons that I failed to understand),

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: Though I knew I should act at once.

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: I puzzled over it, hiding alone,

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: Watching the woman as she neared the gate.

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: He came, and I saw him crouching

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: Night after night.

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: Night after night

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: He came, and I saw him crouching,

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: Watching the woman as she neared the gate.

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: I puzzled over it, hiding alone --

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: Though I knew I should act at once,

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: For reasons that I failed to understand

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: I dared not

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: Put him to flight forever.

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: A closer look (he seemed to turn) might have

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: Revealed in the ragged moon.

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: A momentary glimpse of gleaming eyes

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: A shape amid the shadows,

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: Blackness that moved.

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: Peering furtively from behind a bush,

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: I saw him for the first time,

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: Entering the lonely house with my wife.

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The dialogue "Crab Canon" in Douglas Hofstadter's Gödel, Escher, Bach is nearly a palindrome-by-lines. The second half of the dialog is, with some very minor changes, the same lines as the beginning, in reverse order, spoken by the opposite characters (i.e., lines spoken by Achilles in the first half are spoken by the Tortoise in the second, and vice versa). In the middle is a non-symmetrical line spoken by the Crab, who enters and spouts some nonsense, apparently triggering the reversal. The structure is modeled after J. S. Bach's crab canon.

Related Topics:
Douglas Hofstadter - Gödel, Escher, Bach - J. S. Bach - Crab canon

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Symmetry of dates and times

Palindromes can also be constructed using dates and times. The exact dates and times may differ according to the local style of writing dates and times.

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• 12/02/2021 for the 12th February of 2021, using the (DD/MM/YYYY) format; or the 2nd December of 2021, using the (MM/DD/YYYY) format
• 10/30/2002 03:01 for the 30th October 2002, 3:01 AM, using the (MM/DD/YYYY HH:MM) format

See also

• ambigram
• anagram
• Aoxomoxoa by the Grateful Dead
• crab canon
• pangram
• palindromic number
• transcription (linguistics)
• word games
• word play

External links

• Palindromes
• Palíndromos - In Portuguese.
• Palindromes Quiz
• Jason Doucette - 196 Palindrome Quest / Most Delayed Palindromic Number