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A218026 Shifts 9 places left under Euler transform with a(0)=0 and a(n)=1 for n<9.

%I A218026 #13 May 08 2019 22:17:59
%S A218026 0,1,1,1,1,1,1,1,1,1,1,2,3,5,7,11,15,22,30,42,57,80,109,152,211,296,
%T A218026 415,588,832,1185,1689,2413,3449,4940,7073,10141,14544,20880,29991,
%U A218026 43131,62064,89417,128925,186090,268808,388677,562381,814393,1180070,1711131
%N A218026 Shifts 9 places left under Euler transform with a(0)=0 and a(n)=1 for n<9.
%H A218026 Alois P. Heinz, <a href="/A218026/b218026.txt">Table of n, a(n) for n = 0..1000</a>
%H A218026 N. J. A. Sloane, <a href="/transforms.txt">Transforms</a>
%F A218026 G.f.: x + x^2 + x^3 + x^4 + x^5 + x^6 + x^7 + x^8 + x^9 / Product_{n>=1} (1 - x^n)^a(n). - _Ilya Gutkovskiy_, May 08 2019
%p A218026 with(numtheory):
%p A218026 b:= proc(n) option remember; `if`(n=0, 1,
%p A218026       (add(add(d*a(d), d=divisors(j)) *b(n-j), j=1..n))/n)
%p A218026     end:
%p A218026 a:= n-> `if`(n<9, signum(n), b(n-9)):
%p A218026 seq(a(n), n=0..60);
%Y A218026 Column k=9 of A144018.
%Y A218026 Cf. A316081.
%K A218026 nonn,eigen
%O A218026 0,12
%A A218026 _Alois P. Heinz_, Oct 18 2012