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 A117772 Total number of palindromic primes in base 2 below 2^n. 1
 0, 1, 3, 3, 5, 5, 8, 8, 11, 11, 18, 18, 30, 30, 53, 53, 93, 93, 187, 187, 329, 329, 600, 600, 1080, 1080, 1936, 1936, 3657, 3657, 6756, 6756, 12328, 12328, 23127, 23127, 43909, 43909, 83377, 83377, 156049, 156049, 295916, 295916, 570396, 570396, 1090772 (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 2) and therefore is composite (not prime). Hence there is only one palindromic prime with an even number of digits, namely 11_2 = 3_{10}. LINKS Martin Raab, Table of n, a(n) for n = 1..66 Eric Weisstein: Palindromic Prime. CROSSREFS Cf. A016041, A117697. Sequence in context: A046200 A308415 A063281 * A026924 A240313 A275369 Adjacent sequences:  A117769 A117770 A117771 * A117773 A117774 A117775 KEYWORD nonn,base AUTHOR Martin Renner, Apr 15 2006 EXTENSIONS a(23)-a(40) from Donovan Johnson, Dec 02 2009 Extended to a(66) by Martin Raab, Oct 20 2015 STATUS approved

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Last modified January 22 16:37 EST 2020. Contains 331152 sequences. (Running on oeis4.)