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A003714 Fibbinary numbers: if n = F_i1+F_i2+...+F_ik is the Zeckendorf representation of n (i.e. write n in Fibonacci number system) then a(n) = 2^{i1-2}+2^{i2-2}+...+2^{ik-2}. +0
52
0, 1, 2, 4, 5, 8, 9, 10, 16, 17, 18, 20, 21, 32, 33, 34, 36, 37, 40, 41, 42, 64, 65, 66, 68, 69, 72, 73, 74, 80, 81, 82, 84, 85, 128, 129, 130, 132, 133, 136, 137, 138, 144, 145, 146, 148, 149, 160, 161, 162, 164, 165, 168, 169, 170, 256, 257, 258, 260 (list; graph; listen)
OFFSET

0,3

COMMENT

The name "Fibbinary" is due to Marc LeBrun (mlb(AT)well.com)

"... integers whose binary representation contains no consecutive ones, and noticed that the number of such numbers with n bits was fibonacci(n)" posting to sci.math by Bob Jenkins (bob_jenkins(AT)burtleburtle.net) Jul 17 2002.

n is in the sequence if and only if C(3n,2n) is odd; also a(n) (mod 2) = A003849(n) - Benoit Cloitre, Mar 8 2003

Numbers m such that m XOR 2*m = 3*m. - Reinhard Zumkeller (reinhard.zumkeller(AT)lhsystems.com), May 03 2005. This implies that A003188(2*a(n)) = 3*a(n) holds for all n.

A116361(a(n)) <= 1. - Reinhard Zumkeller (reinhard.zumkeller(AT)lhsystems.com), Feb 04 2006

REFERENCES

Cf. D. E. Knuth, Art of Comp. Programming, Vol. 1, 2nd ed., pp. 85, 493.

LINKS

T. D. Noe, Table of n, a(n) for n=0..1363

Joerg Arndt, Fxtbook

J.-P. Allouche, J. Shallit and G. Skordev, Self-generating sets, integers with missing blocks and substitutions, Discrete Math. 292 (2005) 1-15.

R. Knott, Rabbit Sequence in Zeckendorf Expansion (A003714)

Index entries for sequences defined by congruent products between domains N and GF(2)[X]

Index entries for sequences defined by congruent products under XOR

FORMULA

No two adjacent 1's in binary expansion.

Let f(x) := sum(x^Fibbinary(n), n, 0, inf). Then f satisfies the functional equation f(x) = x f(x^4) + f(x^2).

a(0)=0, a(1)=1, a(2)=2, a(n) = 2^(A072649(n)-1) + a(n - A000045(1+A072649(n))) - Antti Karttunen

It appears that sequence gives n such that A082759(3n) is odd; or, probably equivalently, n such that A037011(3n)=1 - Benoit Cloitre (benoit7848c(AT)orange.fr), Jun 20 2003

If n is in the sequence then so are 2n and 4n+1. - Henry Bottomley (se16(AT)btinternet.com), Jan 11 2005

MAPLE

with(combinat, fibonacci); A003714 := proc(n) option remember; if(n < 3) then RETURN(n); else RETURN((2^(A072649(n)-1))+A003714(n-fibonacci(1+A072649(n)))); fi; end;

MATHEMATICA

f[n_Integer] := Block[{k = Ceiling[ Log[ GoldenRatio, n*Sqrt[5]]], t = n, fr = {}}, While[k > 1, If[t >= Fibonacci[k], AppendTo[fr, 1]; t = t - Fibonacci[k], AppendTo[fr, 0]]; k-- ]; FromDigits[ fr, 2]]; Table[ f[n], {n, 0, 61}] (from Robert G. Wilson v Sep 18 2004)

CROSSREFS

A007088(a(n)) = A014417(n) (same sequence in binary). Complement: A004780. Char. function: A085357. Even terms: A022340, Odd terms: A022341.

Other sequences based on similar restrictions on binary expansion: A003754, A048715, A048718, A107907, A107909.

Cf. A000045, A005203, A005590, A007895, A037011, A048728, A048679, A056017, A060112, A072649, A083368, A089939, A106027, A106028, A116361.

Adjacent sequences: A003711 A003712 A003713 this_sequence A003715 A003716 A003717

Sequence in context: A101185 A045702 A005658 this_sequence A010402 A010443 A035269

KEYWORD

nonn,nice

AUTHOR

njas

EXTENSIONS

Edited Feb 21 2006 by Antti Karttunen (His-Firstname.His-Surname(AT)gmail.com).

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Last modified May 16 23:01 EDT 2008. Contains 139884 sequences.


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