cp's OEIS Frontend

A050030 a(n) = a(n-1) + a(m) for n >= 3, where m = n - 1 - 2^p and p is the unique integer such that 2^p < n - 1 <= 2^(p+1), starting with a(1) = a(2) = 1.

%I A050030 #14 May 10 2020 23:13:34
%S A050030 1,1,2,3,4,5,6,8,11,12,13,15,18,22,27,33,41,42,43,45,48,52,57,63,71,
%T A050030 82,94,107,122,140,162,189,222,223,224,226,229,233,238,244,252,263,
%U A050030 275,288,303,321,343,370,403
%N A050030 a(n) = a(n-1) + a(m) for n >= 3, where m = n - 1 - 2^p and p is the unique integer such that 2^p < n - 1 <= 2^(p+1), starting with a(1) = a(2) = 1.
%H A050030 Ivan Neretin, <a href="/A050030/b050030.txt">Table of n, a(n) for n = 1..8193</a>
%t A050030 Fold[Append[#1, #1[[-1]] + #1[[#2]]] &, {1, 1}, Flatten@Table[k, {n, 0, 5}, {k, 2^n}]] (* _Ivan Neretin_, Sep 06 2015 *)
%o A050030 (PARI) lista(nn) = {nn = max(nn, 2); my(va = vector(nn)); va[1] = 1; va[2] = 1; for(n=3, nn, va[n] = va[n-1] + va[n - 1 - 2^logint(n-2, 2)]); va; } \\ _Petros Hadjicostas_, May 10 2020
%K A050030 nonn
%O A050030 1,3
%A A050030 _Clark Kimberling_
%E A050030 Name edited by _Petros Hadjicostas_, May 10 2020