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%I #11 Mar 05 2015 07:18:00
%S 2,3,5,7,11,23,29,41,47,59,83,101,113,131,137,149,167,191,227,239,257,
%T 263,281,293,311,317,347,353,389,401,419,443,461,479,491,509,563,569,
%U 587,599,617,641,653,659,677,743,761,797,821,839,857,887,911,941,947
%N Chen primes for which the digital root is also a Chen prime.
%e 167 is in the sequence because (1) it is a Chen prime and (2) the digital root 5 is also a Chen prime.
%t digitalRoot[n_Integer?Positive] := FixedPoint[Plus@@IntegerDigits[#] &, n]); chenPrimeQ[x_] := PrimeQ[x] && Plus@@Last/@FactorInteger[x+2] <= 2; Select[Range[1000], chenPrimeQ[#] && chenPrimeQ[digitalRoot[#]]&] (* _Vladimir Joseph Stephan Orlovsky_, Apr 30 2011, with a function by _Eric W. Weisstein_ *)
%o (PARI) isA118723(n)=[0,0,1,1,0,1,0,1,0][n%9+1]&isprime(n)&bigomega(n+2)<3 \\ _Charles R Greathouse IV_, Apr 30 2011
%Y Cf. A109611.
%K base,nonn
%O 1,1
%A Luc Stevens (lms022(AT)yahoo.com), May 21 2006
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