Logo

Greetings from The On-Line Encyclopedia of Integer Sequences!

Hints

Search: id:A143089
Displaying 1-1 of 1 results found. page 1
     Format: long | short | internal | text      Sort: relevance | references | number      Highlight: on | off
A143089 a(n) = a(n - a(n-1)) + a(floor(2*n/3)). +0
2
1, 1, 2, 3, 3, 5, 4, 6, 7, 6, 7, 9, 10, 10, 9, 11, 12, 14, 13, 14, 14, 15, 15, 18, 16, 18, 21, 17, 22, 20, 21, 21, 24, 21, 25, 25, 25, 26, 28, 30, 28, 27, 33, 29, 31, 30, 33, 30, 37, 34, 33, 38, 34, 39, 36, 39, 40, 42, 40, 44, 40, 43, 41, 48, 45, 43, 49, 44, 46, 51, 47, 46, 58, 48 (list; graph; listen)
OFFSET

0,3

MATHEMATICA

Clear[a, f, b, c, g] (*fractal noise chaotic sequence*) f[0] = 1; f[1] = 0; f[1] = 1; f[n_] := f[n] = f[n - f[n - 1]] + f[Floor[2*n/3]] (*Cantor like fractal stair step chaotic sequence*) g[0] = 1; g[1] = 0; g[1] = 1; g[n_] := g[n] = g[Floor[2*n/3]] + g[Floor[n/3]]; ListPlot[Table[{f[n], g[n]}, {n, 0, 200}], PlotJoined -> True]; Table[f[n], {n, 0, 200}]

PROGRAM

(python3) # replace triple dots by spaces; simple, recursive and slow

def A143089(n):

...if n <= 1:

......return 1

...else:

......return A143089(n-A143089(n-1))+A143089(2*n//3)

print([A143089(n) for n in range(0, 80)]) # Oct 18 2009

CROSSREFS

Sequence in context: A163126 A088922 A143092 this_sequence A161857 A135533 A119674

Adjacent sequences: A143086 A143087 A143088 this_sequence A143090 A143091 A143092

KEYWORD

nonn

AUTHOR

Roger L. Bagula (rlbagulatftn(AT)yahoo.com), Oct 16 2008

EXTENSIONS

Corrected offset, adopted OEIS standards of nomenclature - The Assoc. Editors of the OEIS, Oct 18 2009

page 1

Search completed in 0.002 seconds

Lookup | Welcome | Find friends | Music | Plot 2 | Demos | Index | Browse | More | WebCam
Contribute new seq. or comment | Format | Transforms | Puzzles | Hot | Classics
More pages | Superseeker | Maintained by N. J. A. Sloane (njas@research.att.com)

Last modified December 17 23:40 EST 2009. Contains 171025 sequences.


AT&T Labs Research