login
The OEIS Foundation is supported by donations from users of the OEIS and by a grant from the Simons Foundation.

 

Logo


Hints
(Greetings from The On-Line Encyclopedia of Integer Sequences!)
A077965 Expansion of 1/(1+2*x^2-x^3). 2
1, 0, -2, 1, 4, -4, -7, 12, 10, -31, -8, 72, -15, -152, 102, 289, -356, -476, 1001, 596, -2478, -191, 5552, -2096, -11295, 9744, 20494, -30783, -31244, 82060, 31705, -195364, 18650, 422433, -232664, -826216, 887761, 1419768, -2601738, -1951775, 6623244, 1301812, -15198263, 4019620 (list; graph; refs; listen; history; text; internal format)
OFFSET

0,3

LINKS

G. C. Greubel, Table of n, a(n) for n = 0..1000

N. Gogin and A. Mylläri, Padovan-like sequences and Bell polynomials, Proceedings of Applications of Computer Algebra ACA, 2013.

Index entries for linear recurrences with constant coefficients, signature (0,-2,1).

FORMULA

a(0)=1, a(1)=0, a(2)=-2, a(n) = -2*a(n-2)+a(n-3). - Harvey P. Dale, Jan 22 2015

a(n) = (-1)^n * A077967(n). - G. C. Greubel, Jun 24 2019

MATHEMATICA

CoefficientList[Series[1/(1+2x^2-x^3), {x, 0, 50}], x] (* or *) LinearRecurrence[ {0, -2, 1}, {1, 0, -2}, 50] (* Harvey P. Dale, Jan 22 2015 *)

PROG

(PARI) my(x='x+O('x^50)); Vec(1/(1+2*x^2-x^3)) \\ Altug Alkan, Feb 20 2018

(MAGMA) R<x>:=PowerSeriesRing(Integers(), 50); Coefficients(R!( 1/(1+2*x^2-x^3) )); // G. C. Greubel, Jun 24 2019

(Sage) (1/(1+2*x^2-x^3)).series(x, 50).coefficients(x, sparse=False) # G. C. Greubel, Jun 24 2019

(GAP) a:=[1, 0, -2];; for n in [4..50] do a[n]:=-2*a[n-2]+a[n-3]; od; a; # G. C. Greubel, Jun 24 2019

CROSSREFS

Cf. A077967.

Sequence in context: A289918 A127480 A141446 * A077967 A296188 A008312

Adjacent sequences:  A077962 A077963 A077964 * A077966 A077967 A077968

KEYWORD

sign,easy

AUTHOR

N. J. A. Sloane, Nov 17 2002

STATUS

approved

Lookup | Welcome | Wiki | Register | Music | Plot 2 | Demos | Index | Browse | More | WebCam
Contribute new seq. or comment | Format | Style Sheet | Transforms | Superseeker | Recent
The OEIS Community | Maintained by The OEIS Foundation Inc.

License Agreements, Terms of Use, Privacy Policy. .

Last modified February 26 12:43 EST 2020. Contains 332280 sequences. (Running on oeis4.)