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 A054725 #20 Feb 18 2022 20:44:39
%S A054725 1,1,1,2,2,2,2,3,2,3,3,3,3,3,3,4,4,3,3,4,3,4,4,4,4,4,3,4,4,4,4,5,4,5,
%T A054725 4,4,4,4,4,5,5,4,4,5,4,5,5,5,4,5,5,5,5,4,5,5,4,5,5,5,5,5,4,6,5,5,5,6,
%U A054725 5,5,5,5,5,5,5,5,5,5,5,6,4,6,6,5,6,5,5,6,6,5,5,6,5,6,5,6,6,5,5,6,6,6,6,6
%N A054725 a(1)=1; a(n) = Sum_{p | n} e * a(p-1), where sum is over all primes p that divide n, and e is the multiplicity of p in n.
%H A054725 Joerg Arndt, <a href="/A054725/b054725.txt">Table of n, a(n) for n = 1..10000</a>
%F A054725 a(1) = 1 and a(n) = A064415(n) for n>=2. [_Joerg Arndt_, Apr 08 2014]
%e A054725 a(20) = a(2-1) + a(2-1) + a(5-1) = 1 + 1 +2 = 4 because 20 = 2*2*5.
%t A054725 Fold[Append[#1, Total@ Table[#1[[p - 1]], {p, Flatten@ Map[ConstantArray[#1, #2] & @@ # &, FactorInteger[#2]]}]] &, {1}, Range[2, 105]] (* _Michael De Vlieger_, Dec 11 2017 *)
%o A054725 (PARI) a(n)=if (n<=1, 1, my(F=factor(n)); sum(e=1, #F[,1], F[e,2] * a(F[e,1]-1) ) );
%o A054725 vector(200, n, a(n)) \\ _Joerg Arndt_, Apr 08 2014
%K A054725 nonn
%O A054725 1,4
%A A054725 _Leroy Quet_, Apr 20 2000
%E A054725 Title clarified by _Sean A. Irvine_, Feb 18 2022