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%I #10 Oct 11 2019 16:26:56
%S 5,7,7,11,13,11,11,19,13,13,19,17,29,31,17,23,43,19,29,31,23,61,73,41,
%T 37,83,19,47,31,67,53,103,29,17,109,37,127,71,23,139,41,151,83,31,43,
%U 181,193,131,23,101,23,199,29,41,107,19,61,43,37,113,71,229,23,67,241
%N a(n) = A008475(A114520(n)).
%e 24 (which is composite) is the sixth term of sequence A114520. 24 = 2^3 * 3 and 2^3 + 3 = 11 (which is prime). So a(6) = 11.
%t f[n_] := Plus @@ Power @@@ FactorInteger[n]; f /@ Select[Select[Range[500], PrimeQ[f[ # ]] &], ! PrimeQ[ # ] &] (* _Ray Chandler_, Dec 07 2005 *)
%o (PARI) A008475(n)=local(t);if(n<1,0,t=factor(n);sum(k=1,matsize(t)[1],t[k,1]^t[k,2])); for(i=1,900,if(!isprime(i)&&isprime(A008475(i)),print1(A008475(i),","))) (Herrgesell)
%Y Cf. A008475, A114518, A114519, A114520, A047820.
%K nonn
%O 1,1
%A _Leroy Quet_, Dec 05 2005
%E Extended by _Ray Chandler_ and Lambert Herrgesell (zero815(AT)googlemail.com), Dec 07 2005
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