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 A238496 #16 Nov 12 2019 15:06:32
%S A238496 0,0,1,3,8,17,36,73,149,300,602,1205,2413,4827,9656,19314,38632,77265,
%T A238496 154533,309067,618137,1236276,2472554,4945109,9890222,19780446,
%U A238496 39560894,79121791,158243585,316487171,632974345,1265948691,2531897387
%N A238496 Number of prime factors in A052129(n).
%F A238496 a(n) = 2*a(n-1) + A001222(n) for n>=1; a(0) = 0.
%F A238496 a(n) = Sum_{i=1..n} 2^(n-i)*A001222(i). - _Ridouane Oudra_, Nov 11 2019
%p A238496 with(numtheory): seq(add(2^(n-i)*bigomega(i), i=1..n), n=0..40); # _Ridouane Oudra_, Nov 11 2019
%o A238496 (PARI) a(n) = if (n==0, 0, 2*a(n-1) + bigomega(n)); \\ _Michel Marcus_, May 25 2014
%Y A238496 Cf. A001222, A052129, A238462.
%K A238496 nonn,easy
%O A238496 0,4
%A A238496 _Bob Selcoe_, Feb 27 2014