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 A117784 Total number of palindromic primes in base 7 with n digits. 0
 3, 0, 6, 0, 41, 0, 154, 0, 931, 0, 4951, 0, 29932, 0, 180914, 0, 1089138, 0, 6823068, 0, 43644808, 0, 274927477, 0 (list; graph; refs; listen; history; text; internal format)
 OFFSET 1,1 COMMENTS Every palindrome with an even number of digits is divisible by 11 (in base 7) 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. A029975, A117702. Sequence in context: A007385 A307644 A081978 * A257896 A268978 A280585 Adjacent sequences:  A117781 A117782 A117783 * A117785 A117786 A117787 KEYWORD nonn,base AUTHOR Martin Renner, Apr 15 2006 EXTENSIONS a(9)-a(24) from Chai Wah Wu, Dec 26 2015 STATUS approved

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Last modified December 12 15:11 EST 2019. Contains 329960 sequences. (Running on oeis4.)