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 A147981 #9 Apr 25 2020 01:14:38
%S A147981 0,1,1,1,1,2,2,2,2,3,2,3,3,4,4,4,4,3,3,5,3,3,4,5,5,4,4,4,5,5,5,5,5,7,
%T A147981 4,4,6,4,4,4,8,4,4,6,6,6,4,4,4,4,8,8,4,4,4,6,6,6,6,10,10,10,10,10,10,
%U A147981 5,6,7,4,5,9,9,5,5,8,6,6,7,7,5,5,5,10,10,6,6,6,6,7,5,5,6,8,8,4,4,4,6,8,8,4
%N A147981 a(n) = A147952(A004001(n)).
%F A147981 a(n) = A147952(A004001(n)) for n >= 0 with A004001(0) := 0.
%t A147981 (*A004001*) g[0] = 0; g[1] = 1; g[2] = 1; g[n_] := g[n] = g[g[n - 1]] + g[n - g[n - 1]]; (*A147952*) f[0] = 0; f[1] = 1; f[2] = 1; f[n_] := f[n] = f[f[n - 2]] + If[Mod[n, 3] == 0, f[f[n/3]], If[Mod[n, 3] ==1, f[f[(n - 1)/3]], f[n - f[(n - 2)/3]]]]; Table[f[g[n]], {n, 0, 100}]
%Y A147981 Cf. A004001, A147952.
%K A147981 nonn
%O A147981 0,6
%A A147981 _Roger L. Bagula_, Nov 18 2008
%E A147981 Name edited by _Petros Hadjicostas_, Apr 22 2020