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 A269004 #28 Jun 24 2025 16:27:01
%S A269004 1,2,3,5,11,13,12,47,49,24,167,169,503,505,1511,1513,912,432,5879,
%T A269004 5881,600,97,204,118,512,87,148,3886,23291,23293,71,896,11812,60,
%U A269004 41359,2394,11508,5529,8977,200,152681,152683,604,16996,635,40,257,957,79594,517,10155
%N A269004 a(n) is the sum of the prime factors, with repetition, of the sum of all preceding terms, with initial terms a(1)=1 and a(2)=2.
%H A269004 Michael De Vlieger, <a href="/A269004/b269004.txt">Table of n, a(n) for n = 1..5000</a> (first 2000 terms from Paolo P. Lava)
%t A269004 f[x_] := Total@ Flatten[ConstantArray[#1, #2] & @@@ FactorInteger[x]]; s = 3; {1, 2}~Join~Reap[Do[s += Sow@ f[s], {n, 3, 1000}] ][[-1, 1]] (* _Michael De Vlieger_, Jun 24 2025 *)
%o A269004 (PARI) lista(nn) = {va = vector(nn); print1(va[1] = 1, ", "); print1(va[2] = 2, ", "); sp = vecsum(va); for (k=3, nn, f = factor(sp); va[k] = sum(j=1, #f~, f[j, 1]*f[j, 2]); print1(va[k], ", "); sp += va[k]; ); } \\ _Michel Marcus_, Feb 19 2016
%Y A269004 Cf. A001414, A268868 (similar sequence with initial terms 1,1).
%K A269004 nonn
%O A269004 1,2
%A A269004 _David James Sycamore_, Feb 17 2016