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A281014
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Numbers with both prime number of 0's and prime number of 1's in their binary reflected Gray code representation.
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1
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8, 12, 14, 16, 17, 19, 23, 24, 25, 27, 28, 29, 30, 33, 35, 39, 47, 49, 51, 55, 57, 59, 61, 64, 69, 73, 75, 77, 81, 83, 87, 89, 91, 93, 96, 101, 105, 107, 109, 112, 117, 120, 124, 126, 129, 131, 133, 135, 137, 139, 141, 143, 145, 147
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OFFSET
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1,1
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COMMENTS
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LINKS
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EXAMPLE
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27 is in the sequence as it is present in both the sequences A280998 and A280999.
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MATHEMATICA
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Select[Range[150], And @@ PrimeQ[DigitCount[BitXor[#, Floor[#/2]], 2]] &] (* Amiram Eldar, May 01 2021 *)
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PROG
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(PARI) is(n)=isprime(logint(n, 2)-hammingweight(bitxor(n, n>>1))+1) && isprime(hammingweight(bitxor(n, n>>1))) \\ Charles R Greathouse IV, Jan 13 2017
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CROSSREFS
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KEYWORD
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nonn,base,easy
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AUTHOR
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STATUS
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approved
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