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 A117776 Total number of palindromic primes in base 3 with n digits. 0
 1, 0, 2, 0, 3, 0, 12, 0, 8, 0, 47, 0, 106, 0, 280, 0, 720, 0, 1825, 0, 5107, 0, 14072, 0, 38606, 0, 107852, 0, 301048, 0, 852975, 0, 2369097, 0, 6699177, 0, 19111621, 0, 54510099, 0, 155404674, 0 (list; graph; refs; listen; history; text; internal format)
 OFFSET 1,3 COMMENTS Every palindrome with an even number of digits is divisible by 11 (in base 3) and therefore is composite (not prime). Hence there is no palindromic prime with an even number of digits. LINKS Eric Weisstein: Palindromic Prime. CROSSREFS Cf. A029971, A117698. Sequence in context: A308218 A067165 A079981 * A298610 A186492 A137448 Adjacent sequences:  A117773 A117774 A117775 * A117777 A117778 A117779 KEYWORD nonn,base AUTHOR Martin Renner, Apr 15 2006 EXTENSIONS a(15)-a(42) from Chai Wah Wu, Dec 27 2015 STATUS approved

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Last modified January 17 15:12 EST 2020. Contains 330958 sequences. (Running on oeis4.)