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 A118721 Chen primes for which the sum of the digits is also a Chen prime. 1

%I

%S 2,3,5,7,11,23,29,41,47,67,83,89,101,113,131,137,139,157,179,191,197,

%T 199,227,263,269,281,311,317,337,353,359,379,401,409,443,449,461,467,

%U 487,557,571,577,599,641,647,683,719,751,797,809,821,827,829,863,881

%N Chen primes for which the sum of the digits is also a Chen prime.

%H Harvey P. Dale, <a href="/A118721/b118721.txt">Table of n, a(n) for n = 1..1000</a>

%e 29 is in the sequence because (1) it is a Chen prime and (2) the sum of its digits 2+9=11 is also a Chen prime.

%t With[{ch=Select[Prime[Range[200]],PrimeOmega[#+2]<3&]},Select[ch, MemberQ[ ch, Total[IntegerDigits[#]]]&]] (* _Harvey P. Dale_, May 10 2018 *)

%Y Cf. A109611.

%K base,nonn

%O 1,1

%A Luc Stevens (lms022(AT)yahoo.com), May 21 2006

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Last modified April 24 16:06 EDT 2019. Contains 322430 sequences. (Running on oeis4.)