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%I #13 Mar 28 2015 22:36:04
%S 15,21,33,35,39,42,45,51,55,57,63,65,69,75,77,78,84,85,87,91,93,95,99,
%T 105,110,111,114,115,117,119,123,126,129,133,135,141,143,145,147,153,
%U 155,156,159,161,168,170,171,175,177,183,185,186,187,189,195,201,203
%N Arithmetic mean of prime factors of n is an integer and n is neither a prime nor power of a prime.
%H Reinhard Zumkeller, <a href="/A070005/b070005.txt">Table of n, a(n) for n = 1..10000</a>
%e n=33=3*11, mean=(3+11)/2=6.
%t ffi[x_] := Flatten[FactorInteger[x]] lf[x_] := Length[FactorInteger[x]] ba[x_] := Table[Part[ffi[x], 2*w-1], {w, 1, lf[x]}] ep[x_] := Table[Part[ffi[x], 2*w], {w, 1, lf[x]}] Do[s=Apply[Plus, ba[n]]/lf[n]; If[IntegerQ[s]&&Greater[lf[n], 1], Print[n]], {n, 2, 1000}]
%o (Haskell)
%o a070005 n = a070005_list !! (n-1)
%o a070005_list = filter ((== 0) . a010055) a078174_list
%o -- _Reinhard Zumkeller_, Jun 01 2013
%o (PARI) lista(nn) = {for (n=2, nn, f = factor(n); if ((#f~ != 1) && (sum(k=1, #f~, f[k,1]) % #f~ == 0), print1(n, ", ")););} \\ _Michel Marcus_, Mar 28 2015
%Y Cf. A070006, A001414, A008472.
%Y Cf. A000961, A010055; subsequence of A078174.
%K easy,nonn
%O 1,1
%A _Labos Elemer_, Apr 11 2002
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