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A014217 Floor( ((1+sqrt(5))/2)^n ). 32
1, 1, 2, 4, 6, 11, 17, 29, 46, 76, 122, 199, 321, 521, 842, 1364, 2206, 3571, 5777, 9349, 15126, 24476, 39602, 64079, 103681, 167761, 271442, 439204, 710646, 1149851, 1860497, 3010349, 4870846, 7881196, 12752042, 20633239, 33385281 (list; graph; refs; listen; history; internal format)
OFFSET

0,3

COMMENTS

a(n)=L(n)-(1+(-1)^n)/2, where L(n) = Lucas numbers. - Mario Catalani (mario.catalani(AT)unito.it), Jan 17 2003

Floor{lim k->oo {Fibonacci(k)/Fibonacci(k-n)}} - Jon Perry (perry(AT)globalnet.co.uk), Jun 10 2003

For n>1 a(n) is the maximum element in the continued fraction for F(n)*Phi where F=A000045 and Phi=(1+sqrt(5))/2 - Benoit Cloitre (benoit7848c(AT)orange.fr), Jun 19 2005

An integer version of M.S. El Naschie's infinite-dimensional Markov process: d(n) = (1/d(0))^(n - 1); d(0)=(Sqrt[5] - 1)/2. - Roger L. Bagula and Gary W. Adamson (rlbagulatftn(AT)yahoo.com), Aug 08 2008

From 2: successive three evens and three odds. Recurrence a(n)=a(n-1)+2a(n-2)-a(n-3)-a(n-4) also valuable for successive differences ( like for instance a(n)=3a(n-1)-3a(n-2)+2a(n-3) ). See A062724 (2, 2, 3, 5) and A098600 (1, 2, 2). [From Paul Curtz (bpcrtz(AT)free.fr), Sep 20 2008]

a(n+1) = a(n) + a(n-1) + A000035(n+1). [Reinhard Zumkeller, Jan 06 2012]

REFERENCES

Ayman A. El-Okaby, http://arxiv.org/abs/0709.2394, Exceptional Lie Groups, E-infinity Theory and Higgs Boson. - Roger L. Bagula and Gary W. Adamson (rlbagulatftn(AT)yahoo.com), Aug 08 2008

LINKS

T. D. Noe, Table of n, a(n) for n=0..300

G. Harman, One hundred years of normal numbers

Index to sequences with linear recurrences with constant coefficients, signature (1,2,-1,-1).

FORMULA

a(n) = a(n-1) + 2*a(n-2) - a(n-3) - a(n-4). a(n) = a(n-1) + a(n-2) + (1-(-1)^n)/2.

G.f.: (1-x^2+x^3)/((1+x)(1-x)(1-x-x^2)). [From R. J. Mathar (mathar(AT)strw.leidenuniv.nl), Sep 06 2008]

a(2n-1) = (Fibonacci(4n+1)-2)/Fibonacci(2n+2). [From Gary Detlefs (gdetlefs(AT)aol.com), Feb 16 2011]

a(n)=floor(Fibonacci(2n+3)/Fibonacci(n+3)). [From Gary Detlefs (gdetlefs(AT)aol.com), Feb 28 2011]

a(2n)=Fibonacci(2*n-1)+Fibonacci(2*n+1)-1.[From Gary Detlefs (gdetlefs(AT)aol.com), Mar 10 2011]

MATHEMATICA

Table[Floor[GoldenRatio^n], {n, 0, 36}] (* From Vladimir Orlovsky (4vladimir(AT)gmail.com), Dec 12 2008 *)

PROG

(PARI) for (n=0, 20, print1(fibonacci(1000)/(1.0*fibonacci(1000-n))", "))

(MAGMA) [Floor( ((1+Sqrt(5))/2)^n ): n in [0..100]]; // Vincenzo Librandi, Apr 16 2011

(Haskell)

a014217 n = a014217_list !! n

a014217_list = 1 : 1 : zipWith (+)

   a000035_list (zipWith (+) a014217_list $ tail a014217_list)

-- Reinhard Zumkeller, Jan 06 2012

CROSSREFS

Cf. A057146, A062114, A052952, A000045, A020956, A169985, A169986.

Sequence in context: A018144 A115315 A004698 * A034297 A026636 A026658

Adjacent sequences:  A014214 A014215 A014216 * A014218 A014219 A014220

KEYWORD

nonn,easy,nice

AUTHOR

Clark Kimberling (ck6(AT)evansville.edu)

EXTENSIONS

Corrected by T. D. Noe (noe(AT)sspectra.com), Nov 09 2006

Edited by N. J. A. Sloane (njas(AT)research.att.com), Aug 29 2008 at the suggestion of R. J. Mathar

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Last modified February 17 00:09 EST 2012. Contains 205978 sequences.