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A172986 a(0) = 0, a(n) = A029826(n+1) for n <= 20, otherwise a(n) = a(n - 1 - n % 20) + A029826(2 + n % 20 ).

%I A172986 #7 Dec 17 2022 06:51:08
%S A172986 0,1,-1,1,0,0,1,0,1,0,1,1,1,1,2,1,2,3,2,4,3,3,5,4,4,5,4,5,4,5,5,5,5,6,
%T A172986 5,6,7,6,8,7,8,6,8,7,7,8,7,8,7,8,8,8,8,9,8,9,10,9,11,10,11,9,11,10,10,
%U A172986 11,10,11,10,11,11,11,11,12,11,12,13,12,14,13,14,12,14,13,13,14,13,14,13
%N A172986 a(0) = 0, a(n) = A029826(n+1) for n <= 20, otherwise a(n) = a(n - 1 - n % 20) + A029826(2 + n % 20 ).
%t A172986 p[x_] = (x^(10) + x^9 - x^7 - x^6 - x^5 - x^4 - x^3 + x + 1);
%t A172986 q[x_] = Expand[x^10*p[1/x]];
%t A172986 a = Table[SeriesCoefficient[Series[1/q[x], {x, 0, 50}], n], {n, 0, 20}];
%t A172986 b[0] := 0;
%t A172986 b[n_] := b[n] = If[n <= 20, a[[n]], b[n - 1 - Mod[n, 20]] + a[[1 + Mod[n, 20]]]];
%t A172986 Table[b[n], {n, 0, 100}]
%Y A172986 Cf. A029826.
%K A172986 sign,base,less
%O A172986 0,15
%A A172986 _Roger L. Bagula_, Feb 06 2010