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A099496 (-1)^n*Fib(2n+1). 3
1, -2, 5, -13, 34, -89, 233, -610, 1597, -4181, 10946, -28657, 75025, -196418, 514229, -1346269, 3524578, -9227465, 24157817, -63245986, 165580141, -433494437, 1134903170, -2971215073, 7778742049, -20365011074, 53316291173, -139583862445, 365435296162, -956722026041 (list; graph; refs; listen; history; internal format)
OFFSET

0,2

COMMENTS

With interpolated zeros, a Chebyshev transform of A056594, which has g.f. 1/(1+x^2). The image of G(x) under the Chebyshev transform is (1/(1+x^2))G(x/(1+x^2)).

Contribution from Adam Helman (helman(AT)san.rr.com), May 09 2010: (Start)

a(n) is the ceiling of the INVERSE FRACTIONAL ERROR in approximating phi,

the golden section, by the ratio of two successive terms in the Fibonacci series.

(End)

LINKS

Index entries for sequences related to linear recurrences with constant coefficients

Tanya Khovanova, Recursive Sequences

FORMULA

G.f.: (1+x)/(1+3x+x^2);(with interpolated zeros) (1+x^2)/(1+3x^2+x^4); a(n)=sum{k=0..floor(n/2), binomial(n-k, k)(-1)^k*cos((n-2k)*pi/2)} (with interpolated zeros); a(n)=F(n+1)(-1)^(n/2)(1+(-1)^n)/2 (with interpolated zeros).

a(n)=[(-1)^n]*[Sum{k=0..n+1}(binomial(n+k,n-k)], with n>=0 - Paolo P. Lava (paoloplava(AT)gmail.com), Apr 13 2007

a(n)=-3*a(n-1)-a(n-2),a(0)=1, a(1)=-2. [From Philippe DELEHAM (kolotoko(AT)wanadoo.fr), Nov 03 2008]

Contribution from Adam Helman (helman(AT)san.rr.com), May 09 2010: (Start)

a(n) = ceil( phi / [F_{n+1}/F_n - phi] ).

An exact expression for the inverse fractional error is

phi / [F_{n+1}/F_n - phi] = (phi/sqrt(5)) * [(-1)^n *{phi^2n} - 1]. (End)

a(n) = (-1)^n*A122367(n). [From R. J. Mathar (mathar(AT)strw.leidenuniv.nl), Jul 23 2010]

EXAMPLE

Contribution from Adam Helman (helman(AT)san.rr.com), May 09 2010: (Start)

The first term: a(1) = ceil( phi / [F_2/F_1 - phi] ) = -2. (End)

MATHEMATICA

lst={}; Do[AppendTo[lst, (-1)^n*Fibonacci[2*n+1]], {n, 5!}]; lst [From Vladimir Orlovsky (4vladimir(AT)gmail.com), Jan 18 2009]

CROSSREFS

Sequence in context: A001519 A122367 A048575 * A114299 A112842 A097417

Adjacent sequences:  A099493 A099494 A099495 * A099497 A099498 A099499

KEYWORD

easy,sign

AUTHOR

Paul Barry (pbarry(AT)wit.ie), Oct 19 2004

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Last modified February 23 09:08 EST 2012. Contains 206628 sequences.