%I #11 May 09 2019 07:24:20
%S 0,1,1,1,1,1,1,1,1,1,1,1,2,2,3,4,5,6,8,10,12,16,20,26,35,45,59,79,104,
%T 137,183,242,320,427,567,754,1008,1345,1797,2409,3228,4328,5817,7817,
%U 10511,14154,19063,25689,34655,46768,63148,85336,115372,156057,211233
%N Sequence shifts left nine places under Weigh transform with a(n) = signum(n) for n<9.
%H Alois P. Heinz, <a href="/A316081/b316081.txt">Table of n, a(n) for n = 0..2500</a>
%F 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 09 2019
%p b:= proc(n, i) option remember; `if`(n=0, 1, `if`(i<1, 0,
%p add(binomial(a(i), j)*b(n-i*j, i-1), j=0..n/i)))
%p end:
%p a:= n-> (k-> `if`(n<k, signum(n), b(n-k$2)))(9):
%p seq(a(n), n=0..54);
%Y Column k=9 of A316074.
%Y Cf. A057427, A218026.
%K nonn,eigen
%O 0,13
%A _Alois P. Heinz_, Jun 23 2018
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