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 A281382 Numbers n such that the decimal equivalent of the binary reflected Gray code representation of n is a palindromic prime. 2
 2, 3, 5, 6, 13, 70, 213, 217, 229, 253, 422, 426, 446, 465, 534, 541, 705, 741, 857, 869, 8441, 8481, 9190, 9221, 9293, 10210, 10349, 10453, 10929, 11049, 12006, 12281, 12329, 12721, 12793, 14109, 14282, 20578, 20934, 21009, 21629, 21701, 22810, 22866, 23221, 23421, 28705, 29397 (list; graph; refs; listen; history; text; internal format)
 OFFSET 1,1 COMMENTS Numbers n such that A003188(n) is both prime and palindromic. LINKS Indranil Ghosh and Chai Wah Wu, Table of n, a(n) for n = 1..13824, first 1281 terms from Indranil Ghosh. EXAMPLE 213 is in the sequence because A003188(213) = 191 and 191 is a palindromic prime. MATHEMATICA Select[Range@ 30000, And[PrimeQ@ #, Reverse@ # == # &@ IntegerDigits@ #] &@ BitXor[#, Floor[#/2]] &] (* Michael De Vlieger, Mar 30 2017 *) PROG (Python) from sympy import isprime def G(n): ....return int(bin(n^(n/2))[2:], 2) i=0 j=1 while j<=1281: ....if G(i)==int(str(G(i))[::-1]) and isprime(G(i))==True: ........print str(j)+" "+str(i) ........j+=1 ....i+=1 CROSSREFS Cf. A002385, A003188. Sequence in context: A075371 A218948 A057704 * A078203 A285937 A253647 Adjacent sequences:  A281379 A281380 A281381 * A281383 A281384 A281385 KEYWORD nonn,base AUTHOR Indranil Ghosh, Jan 21 2017 STATUS approved

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Last modified April 24 10:24 EDT 2019. Contains 322422 sequences. (Running on oeis4.)