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%I #4 Oct 31 2013 12:17:39
%S 2,3,5,7,13,17,31,37,53,71,113,131,137,157,211,311,317,359,389,431,
%T 557,571,751,827,839,953,983,1117,1151,1297,1367,1511,1553,1621,1637,
%U 1759,2111,2179,2213,2269,2339,2393,2699,2719,2969,2971,3167,3221,3329,3511
%N Chen primes for which the multiplicative digital root is also a Chen prime.
%e 157 is in the sequence because (1) it is a Chen prime and (2) the multiplicative digital root 5 is also a Chen prime.
%t mdr[n_] := NestWhile[Times @@ IntegerDigits@# &, n, # > 9 &]; chenQ[n_] := PrimeQ[n] && Plus @@ Last /@ FactorInteger[n + 2] < 3; Select[ Prime@ Range@500, chenQ@ mdr@# && chenQ@# &] (* _Robert G. Wilson v_ *)
%Y Cf. A109611.
%K base,nonn
%O 1,1
%A Luc Stevens (lms022(AT)yahoo.com), May 21 2006
%E More terms from _Robert G. Wilson v_, May 22 2006