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 A084201 Primes n such that the sum of the digits is prime and the sum of the digits of 2n is also prime. 0

%I

%S 7,29,47,61,83,137,139,151,173,191,193,227,229,263,281,283,317,337,

%T 353,373,409,461,463,557,577,599,601,641,643,733,757,797,821,823,887,

%U 911,977,1019,1039,1051,1091,1093,1109,1129,1163,1181,1217,1237,1291

%N Primes n such that the sum of the digits is prime and the sum of the digits of 2n is also prime.

%C Note that 137 and 139 are twin primes.

%C A049084(A007953(a(n)))*A049084(A007953(2*a(n))) > 0. - _Reinhard Zumkeller_, Jun 26 2003

%e 2+9=11=prime for 29 and 5+8=13=prime for 58=2*29;

%e 1+3+7=11=prime for 137 and 2+7+4=13=prime for 274=2*137;

%e 1+3+9=13=prime for 139 and 2+7+8=17=prime for 278=2*139.

%t Select[Prime[Range[300]],And@@PrimeQ[Total/@{IntegerDigits[#], IntegerDigits[2 #]}]&] (* _Harvey P. Dale_, Jun 26 2011 *)

%K base,nonn

%O 0,1

%A _Patrick Capelle_, Jun 20 2003

%E More terms from _Reinhard Zumkeller_, Jun 26 2003

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Last modified July 23 15:58 EDT 2019. Contains 325258 sequences. (Running on oeis4.)