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 A330900 #14 Feb 17 2024 11:31:34 %S A330900 0,2,22,130,1196,11698,107315,961924,8641491,78304633,714962670, %T A330900 6572968299 %N A330900 Number of terms of A066038 that do not exceed 10^n. %C A330900 Luca & Moodley (2020) conjectured that a(n) ~ exp(gamma) * A006880(n). %H A330900 Florian Luca and Damon Moodley, <a href="http://dx.doi.org/10.5817/AM2020-1-49">Composite positive integers whose sum of prime factors is prime</a>, Archivum Mathematicum, Vol. 56, No. 1 (2020), pp. 49-64. %e A330900 There are 2 terms of A066038 not exceeding 10^1: 6 and 10. Thus a(1) = 2. %t A330900 b[1] = 0; b[n_] := Plus @@ FactorInteger[n][[;; , 1]]; bQ[n_] := PrimeNu[n] > 1 && PrimeQ[b[n]]; p = 1; s = 0; seq = {}; Do[If[bQ[n], s++]; If[n == p, p *= 10; AppendTo[seq, s]], {n, 1, 10^6}]; seq %Y A330900 Cf. A006880, A008472, A066038, A073004. %K A330900 nonn,more %O A330900 0,2 %A A330900 _Amiram Eldar_, May 01 2020 %E A330900 a(11) from _Giovanni Resta_, May 05 2020