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 A117697 Palindromic primes in base 2 (written in base 2). 9
 11, 101, 111, 10001, 11111, 1001001, 1101011, 1111111, 100000001, 100111001, 110111011, 10010101001, 10110101101, 11000100011, 11001010011, 11011111011, 11100100111, 11101010111, 1001100011001, 1001111111001, 1010001000101 (list; graph; refs; listen; history; text; internal format)
 OFFSET 1,1 LINKS Attila Olah, Table of n, a(n) for n=1..43964 Eric Weisstein: Palindromic Prime. FORMULA a(n) = A007088(A016041(n)). - R. J. Mathar, Feb 25 2007 MAPLE isA016041 := proc(n)     local bin, dig ;     if isprime(n) then         bin := convert(n, base, 2) ;         for dig from 1 to nops(bin)/2 do             if op(dig, bin) <> op(-dig, bin) then                 return false;             end if;         end do ;         return true;     else         false ;     end if ; end proc: for i from 1 to 900 do p := ithprime(i) : if isA016041(p) then printf("%d, ", A007088(p)) ; fi ; od : # R. J. Mathar, Feb 25 2007 MATHEMATICA pal2Q[n_] := Reverse[x = IntegerDigits[n, 2]] == x; BaseForm[Select[Prime[Range[700]], pal2Q[#] &], 2] (* Jayanta Basu, Jun 24 2013 *) CROSSREFS Cf. A016041, A002385. Sequence in context: A076289 A247647 A240602 * A305395 A091366 A158051 Adjacent sequences:  A117694 A117695 A117696 * A117698 A117699 A117700 KEYWORD nonn,base AUTHOR Martin Renner, Apr 13 2006 EXTENSIONS Keyword:base added by R. J. Mathar, Jul 12 2009 STATUS approved

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Last modified February 18 10:13 EST 2019. Contains 320250 sequences. (Running on oeis4.)