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World!Of Palindromic Primes
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Palindromic Primes are primes that read the same
 p_right left to right (forwards) as from the right to left (backwards) p_left
Here are a few random examples : 3, 131, 71317, 134757431

This study exposes some statistics concerning palindromic primes.
For every length it gives the total number of existing palindromic primes
as well the smallest and greatest primes for those lengths.
Also in this section, now dispersed over five pages, you'll find a variety of
facts and figures about palindromic primes. Don't look for a logical order. It is
just an amalgamation of randomly gathered curios, puzzles, contributions and
more general information. I hope you  Enjoy  them !

Table of Contents

    Palprime Page  1 
  • Palindromic Prime Statistics
    • the table itself - co-authors Martin Eibl, Carlos Rivera and Warut Roonguthai
    • palindromic primes of length 3 (total 15)
    • palindromic primes of length 5 (total 93)
    • palindromic primes of length 7 (the "Twin Pairs")
  • Every palindrome (except 11) with an even number of digits is composite

    Palprime Page  2 
  • The record proven palindromic prime - now 1888529 digits long ! by Ryan Propper and Serge Batalov
  • Harvey Dubner's
    • picture sitting at his computer
    • HD's former palindromic prime records
    • doubly palindromic prime record (with palindromic prime length) - now 98689 digits long !

    Palprime Page  3 
  • Harvey Dubner's
    • palindromic primes in 'arithmetic progression'
    • palindromic Sophie Germain primes
  • Warut Roonguthai's
    • smallest palindromic primes in 'arithmetic progression'
  • Nicholas Angelou's
    • straightforward plateau palprimes
  • Various puzzles, facts and figures, discoveries from
    • G. L. Honaker, Jr. - Palindromic Prime Pyramid Puzzle
    • Patrick De Geest - About 13331 - About 134757431 - Smallest primes that are palindromic
    • Carlos Rivera & Jaime Ayala - Magic Squares - Sums of three consecutive palprimes - About 71317
    • Enoch Haga - Palprimes in M37 (the 37th Mersenne prime)
    • G. L. Honaker, Jr. - Trinity of the Beast - Honaker's Constant - Some nice palprimes
    • Mike Keith - Descriptive primes

    Palprime Page  4 
  • A closer look at the fifteen threedigit palprimes
    • About palprime 313 - or Enoch Haga's Number of the Duck and more
    • About palprime 353
    • About palprime 373
    • About palprime 383

    Palprime Page  5 
  • Palindromic Primes embedded between equal single digits
    • by Zakir Seidov
  • Some Palindromic Primes Assignments
    • Admire Jud McCranie's solutions for assignment 2
  • Sources Revealed and Related Internet Sites
    • Integer Sequences about Palprimes in Neil Sloane's Online Encyclopedia
    • Various book and web sources, reference material

    Palprime Page  6 
  • Sequence building by concatenating ascending and descending palindromes
    • Explorations and Pari/gp code by Patrick De Geest

Article contributions

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triangle tetra square cube circular palpri
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( © All rights reserved ) - Last modified : January 12, 2022.
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