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 A007441 M0201 #28 Jul 08 2025 17:04:25
%S A007441 1,-2,-2,1,3,7,5,6,-10,-27,-50,-42,-30,41,148,241,345,303,167,-275,
%T A007441 -858,-1685,-2342,-2813,-2316,-536,2914,8228,14531,20955,24370,22393,
%U A007441 10265,-13839,-53386,-104364,-161593,-209463,-228141,-188750,-62023,177547,541310,1009998,1527972,1976120,2189974
%N A007441 1 + Sum_{n>=1} a_n x^n = Product_{n>=1} (1-x^n)^prime(n).
%D A007441 N. J. A. Sloane and Simon Plouffe, The Encyclopedia of Integer Sequences, Academic Press, 1995 (includes this sequence).
%H A007441 Seiichi Manyama, <a href="/A007441/b007441.txt">Table of n, a(n) for n = 0..10000</a>
%F A007441 a(n) = (1/n)*Sum_{k=1..n} a(n-k)*b(k), k>0, a(0)=1, b(k)=-Sum_{d|k} d*prime(d), cf. A061150.
%Y A007441 Cf. A030009, A030010, A061150, A061151, A061152.
%K A007441 sign
%O A007441 0,2
%A A007441 _N. J. A. Sloane_
%E A007441 Better description from _Vladeta Jovovic_, Apr 16 2001