This is a front-end for the Online Encyclopedia of Integer Sequences, made by Christian Perfect. The idea is to provide OEIS entries in non-ancient HTML, and then to think about how they're presented visually. The source code is on GitHub.
%I A114520 #10 Oct 11 2019 16:27:21 %S A114520 6,10,12,18,22,24,28,34,36,40,48,52,54,58,72,76,82,88,100,108,112,118, %T A114520 142,148,160,162,165,172,184,192,196,202,208,210,214,232,250,268,273, %U A114520 274,288,298,316,345,352,358,382,384,385,388,390,394,399,400,412,420 %N A114520 Composites in sequence A114518. %e A114520 24 is a composite. 24 = 2^3 * 3 and 2^3 + 3 = 11, which is prime. So 24 is in the sequence. %t A114520 f[n_] := Plus @@ Power @@@ FactorInteger[n]; Select[Select[Range[425], PrimeQ[f[ # ]] &], ! PrimeQ[ # ] &] (* _Ray Chandler_, Dec 07 2005 *) %o A114520 (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=1,700,if(!isprime(i)&&isprime(A008475(i)),print1(i,","))) (Herrgesell) %Y A114520 Cf. A008475, A114518, A114521, A047820. %K A114520 nonn %O A114520 1,1 %A A114520 _Leroy Quet_, Dec 05 2005 %E A114520 Extended by _Ray Chandler_ and Lambert Herrgesell (zero815(AT)googlemail.com), Dec 07 2005