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A140472 Chaotic sequence related to A004001: a(n)=a(n-a(n-1))+a(Floor[n/2]]. 2
0, 1, 2, 2, 4, 3, 4, 4, 8, 5, 6, 6, 8, 7, 8, 8, 16, 9, 10, 10, 12, 11, 12, 12, 16, 13, 14, 14, 16, 15, 16, 16, 32, 17, 18, 18, 20, 19, 20, 20, 24, 21, 22, 22, 24, 23, 24, 24, 32, 25, 26, 26, 28, 27, 28, 28, 32, 29, 30, 30, 32, 31, 32, 32, 64, 33, 34, 34, 36, 35, 36, 36, 40, 37, 38 (list; graph; refs; listen; history; text; internal format)
OFFSET

0,3

COMMENTS

The sequence appears to have a peak-like (von Koch?) self-similar structure.

LINKS

Reinhard Zumkeller, Table of n, a(n) for n = 0..10000

FORMULA

a(0)=0;a(1)=a(2)=1; a(n)=a(n-a(n-1))+a(Floor[n/2]]

MATHEMATICA

f[0] = 0; f[1] = 1; f[1] = 1; f[n_] := f[n] = f[n - f[n - 1]] + f[Floor[n/2]]; b = Table[f[n], {n, 0, 200}]

PROG

(Haskell)

a140472 n = a140472_list !! n

a140472_list = 0 : 1 : h 2 1 where

  h x y = z : h (x + 1) z where z = a140472 (x - y) + a140472 (x `div` 2)

-- Reinhard Zumkeller, Jul 20 2012

CROSSREFS

Cf. A004001.

Cf. A214546 (first differences).

Sequence in context: A117484 A086835 A046701 * A109168 A015134 A171580

Adjacent sequences:  A140469 A140470 A140471 * A140473 A140474 A140475

KEYWORD

nonn

AUTHOR

Roger L. Bagula and Gary W. Adamson, Jun 28 2008

EXTENSIONS

Offset corrected by Reinhard Zumkeller, Jul 20 2012

STATUS

approved

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Last modified April 18 18:34 EDT 2014. Contains 240732 sequences.