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Composite numbers the sum of the digits in the prime factors of which, with repetition, is prime.
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%I #9 Sep 15 2016 11:15:52

%S 6,10,12,28,33,39,40,45,46,48,51,54,55,56,57,58,63,66,75,80,82,85,90,

%T 91,93,94,96,102,108,111,130,133,147,154,156,159,166,172,175,177,178,

%U 182,184,190,207,210,213,217,219,220,224,226,228,232,237,238,244,245

%N Composite numbers the sum of the digits in the prime factors of which, with repetition, is prime.

%H Harvey P. Dale, <a href="/A064166/b064166.txt">Table of n, a(n) for n = 0..1000</a>

%e 220 is included because 220 = 2*2*5*11 and 2+2+5+1+1 = 11, which is prime.

%t cnpQ[n_]:=CompositeQ[n]&&PrimeQ[Total[Flatten[IntegerDigits/@(Table[ #[[1]], #[[2]]]&/@FactorInteger[n])]]]; Select[Range[250],cnpQ] (* _Harvey P. Dale_, Sep 15 2016 *)

%K nonn,base

%O 0,1

%A _Harvey P. Dale_, Sep 19 2001