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A000360 From a fat-fractal triangle which happens to be a self-replicating tiling. 3
1, 0, 1, 1, 1, 1, 2, 0, 2, 2, 2, 1, 3, 1, 2, 1, 2, 2, 4, 1, 4, 3, 3, 1, 4, 2, 4, 2, 3, 2, 3, 0, 3, 3, 4, 2, 6, 3, 5, 2, 5, 4, 7, 2, 6, 4, 4, 1, 5, 3, 6, 3, 6, 4, 6, 1, 5, 4, 5, 2, 5, 2, 3, 1, 3, 3, 6, 2, 7, 5, 6, 2, 8, 5, 9, 4, 8, 5, 7, 1, 7, 6, 9, 4, 11, 6, 9, 3, 8, 6, 10, 3, 8, 5, 5, 1, 6, 4, 8, 4, 9, 6, 9, 2 (list; graph; refs; listen; history; text; internal format)
OFFSET

0,7

REFERENCES

Melvyn J. Lafitte, Sur l'Effet Noa`h en Geometrie, rapport a l'INPI, Mars 1995.

Melvyn J. Lafitte, Ensembles Auto-Similaires d'Interieur Non-Vide, Preprint Hiver 1997, Chaire de Geometrie, Departement de Mathematiques, Ecole Polytechnique Federale de Lausanne, Switzerland.

LINKS

T. D. Noe, Table of n, a(n) for n = 0..10000

FORMULA

a(0) = 1, a(2n) = a(n) + a(n-1), a(2n+1) = a(n) + 1 - (n-1 mod 3). - Ralf Stephan, Oct 05 2003

MATHEMATICA

a[0] = 1; a[n_?EvenQ] := a[n] = a[n/2] + a[n/2-1]; a[n_?OddQ] := a[n] = a[(n-1)/2] - Mod[(n-1)/2-1, 3] + 1; Table[a[n], {n, 0, 103}] (* Jean-Fran├žois Alcover, Jan 20 2015, after Ralf Stephan *)

PROG

(Haskell)

import Data.List (transpose)

a000360 n = a000360_list !! n

a000360_list = 1 : concat (transpose

   [zipWith (+) a000360_list $ drop 2 a057078_list,

    zipWith (+) a000360_list $ tail a000360_list])

-- Reinhard Zumkeller, Mar 22 2013

CROSSREFS

Related to A002487 by new(3n)=(old(3n)+1)/2, new(3n+1)=(old(3n+1)-1)/2, new(3n+2)=old(3n+2)/2. Cf. A000361, A000876.

Cf. A057078.

Sequence in context: A127504 A047917 A144569 * A023556 A238783 A044944

Adjacent sequences:  A000357 A000358 A000359 * A000361 A000362 A000363

KEYWORD

nonn,nice,easy,eigen,look

AUTHOR

Melvyn Jeremie Lafitte (mjlafitte(AT)gmail.com)

EXTENSIONS

More terms from David W. Wilson, Aug 30 2000

STATUS

approved

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Last modified March 28 02:40 EDT 2017. Contains 284182 sequences.