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Search: id:A016115
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| A016115 |
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Number of prime palindromes with n digits. |
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+0
5
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| 4, 1, 15, 0, 93, 0, 668, 0, 5172, 0, 42042, 0, 353701, 0, 3036643, 0, 27045226, 0, 239093865, 0, 2158090933, 0
(list; graph; listen)
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OFFSET
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1,1
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COMMENT
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Every palindrome with an even number of digits is divisible by 11 and therefore is composite (not prime). Hence there is only one palindromic prime with an even number of digits. - Martin Renner (martin.renner(AT)gmx.net), Apr 15 2006
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LINKS
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K. S. Brown, On General Palindromic Numbers
P. De Geest, World!Of Palindromic Primes
Shyam Sunder Gupta, Palindromic Primes up to 10^19.
Eric Weisstein's World of Mathematics, Link to a section of The World of Mathematics.
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CROSSREFS
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Cf. A002385, A040025.
Adjacent sequences: A016112 A016113 A016114 this_sequence A016116 A016117 A016118
Sequence in context: A050156 A096644 A145829 this_sequence A164794 A107873 A156290
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KEYWORD
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nonn,hard,base
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AUTHOR
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Robert G. Wilson v (rgwv(AT)rgwv.com)
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EXTENSIONS
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Corrected and extended by Patrick De Geest (pdg(AT)worldofnumbers.com), Jun 15 1998.
'27045226' was found in collaboration with Martin Eibl (M.EIBL(AT)LINK-R.de), Carlos Rivera (crivera(AT)ux1.sci.net.mx), Warut Roonguthai (warut822(AT)yahoo.com)
a(19) from Shyam Sunder Gupta (guptass(AT)rediffmail.com), Feb 12 2006
a(21) - a(22) from Shyam Sunder Gupta (guptass(AT)rediffmail.com), Mar 13 2009
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