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A050026 a(n) = a(n-1) + a(m) for n >= 4, 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) = a(3) = 1. 4
1, 1, 1, 2, 3, 4, 5, 6, 8, 9, 10, 11, 13, 16, 20, 25, 31, 32, 33, 34, 36, 39, 43, 48, 54, 62, 71, 81, 92, 105, 121, 141, 166, 167, 168, 169, 171, 174, 178, 183, 189, 197, 206, 216, 227, 240, 256, 276, 301 (list; graph; refs; listen; history; text; internal format)
OFFSET

1,4

LINKS

Ivan Neretin, Table of n, a(n) for n = 1..8193

MATHEMATICA

Fold[Append[#1, #1[[-1]] + #1[[#2]]] &, {1, 1, 1}, Flatten@Table[k, {n, 5}, {k, 2^n}]] (* Ivan Neretin, Aug 30 2015 *)

PROG

(PARI) lista(nn) = {nn = max(nn, 3); my(va = vector(nn)); va[1] = 1; va[2] = 1; va[3] = 1; for(n=4, nn, va[n] = va[n-1] + va[n - 1 - 2^logint(n-2, 2)]); va; } \\ Petros Hadjicostas, May 03 2020

CROSSREFS

Sequence in context: A153134 A220506 A045546 * A328413 A174788 A129143

Adjacent sequences:  A050023 A050024 A050025 * A050027 A050028 A050029

KEYWORD

nonn

AUTHOR

Clark Kimberling

EXTENSIONS

Name edited by Petros Hadjicostas, Apr 25 2020

STATUS

approved

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Last modified September 27 18:56 EDT 2021. Contains 347694 sequences. (Running on oeis4.)