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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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