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%I #17 Jul 20 2020 02:16:47
%S 1,2,2,4,8,10,14,24,48,50,54,64,88,138,202,340,680,682,686,696,720,
%T 770,834,972,1312,1994,2690,3460,4432,6426,9886,16312,32624,32626,
%U 32630,32640,32664,32714,32778,32916,33256,33938,34634
%N a(n) = a(n-1) + a(m) for n >= 4, where m = 2*n - 2 - 2^(p+1) and p is the unique integer such that 2^p < n - 1 <= 2^(p+1), starting with a(1) = 1 and a(2) = a(3) = 2.
%H Ivan Neretin, <a href="/A050047/b050047.txt">Table of n, a(n) for n = 1..8193</a>
%t Fold[Append[#1, #1[[-1]] + #1[[#2]]] &, {1, 2, 2}, Flatten@Table[2 k, {n, 5}, {k, 2^n}]] (* _Ivan Neretin_, Sep 06 2015 *)
%o (PARI) lista(nn) = {nn = max(nn, 3); my(va = vector(nn)); va[1] = 1; va[2] = 2; va[3] = 2; for(n=4, nn, va[n] = va[n-1] + va[2*(n - 1 - 2^logint(n-2, 2))]); va; } \\ _Petros Hadjicostas_, Jul 19 2020
%Y Cf. A050027, A050031, A050035, A050039, A050043, A050051, A050055, A050059, A050063, A050067, A050071 (similar, but with different initial conditions).
%K nonn
%O 1,2
%A _Clark Kimberling_
%E Name edited by _Petros Hadjicostas_, Jul 19 2020
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