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 A108606 Semiprimes with prime sum of digits. 3

%I

%S 14,21,25,34,38,49,58,65,74,85,94,106,111,115,119,122,133,142,146,155,

%T 166,201,203,205,209,214,218,221,247,254,265,274,278,287,289,298,302,

%U 319,326,335,346,355,362,371,377,382,386,391,395,403,407,427,445,454

%N Semiprimes with prime sum of digits.

%C 34 is the smallest term in common with A108605. Cf. A001358 semiprimes, A101605 3-almost primes, A108605 semiprimes with prime sum of factors, A108607 intersection of A108605 and A108606.

%e 34=2*17 (semiprime) and 2+17=19 is prime.

%t A108606=Select[Range[1000], Plus@@(Transpose[FactorInteger[ # ]])[[2]]==2&& PrimeQ[Plus@@IntegerDigits[ # ]]&]

%Y Cf. A001358, A101605, A108606, A108607.

%K nonn,base

%O 1,1

%A _Zak Seidov_, Jun 12 2005

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Last modified October 18 03:16 EDT 2019. Contains 328135 sequences. (Running on oeis4.)