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1 + Sum_{n>=1} a_n x^n = Product_{n>=1} (1-x^n)^prime(n).
(Formerly M0201)
9

%I M0201 #24 Oct 29 2023 09:45:53

%S 1,-2,-2,1,3,7,5,6,-10,-27,-50,-42,-30,41,148,241,345,303,167,-275,

%T -858,-1685,-2342,-2813,-2316,-536,2914,8228,14531,20955,24370,22393,

%U 10265,-13839,-53386,-104364,-161593,-209463,-228141,-188750,-62023,177547,541310,1009998,1527972,1976120,2189974

%N 1 + Sum_{n>=1} a_n x^n = Product_{n>=1} (1-x^n)^prime(n).

%D N. J. A. Sloane and Simon Plouffe, The Encyclopedia of Integer Sequences, Academic Press, 1995 (includes this sequence).

%H Seiichi Manyama, <a href="/A007441/b007441.txt">Table of n, a(n) for n = 0..10000</a>

%F 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 Cf. A030009, A030010, A061150, A061151, A061152.

%K sign

%O 0,2

%A _N. J. A. Sloane_.

%E Better description from _Vladeta Jovovic_, Apr 16 2001