A077918 Expansion of (1 - x)^(-1)/(1 + 2*x - 2*x^2 + x^3).

1, -1, 5, -12, 36, -100, 285, -805, 2281, -6456, 18280, -51752, 146521, -414825, 1174445, -3325060, 9413836, -26652236, 75457205, -213632717, 604832081, -1712386800, 4848070480, -13725746640, 38860021041, -110019605841, 311485000405, -881869233532, 2496728073716, -7068679614900

Offset

0,3

Links

Vincenzo Librandi, Table of n, a(n) for n = 0..1000

Index entries for linear recurrences with constant coefficients, signature (-1,4,-3,1).

Mathematica

CoefficientList[Series[(1-x)^(-1)/(1+2x-2x^2+x^3), {x, 0, 30}], x] (* or *) LinearRecurrence[{-1, 4, -3, 1}, {1, -1, 5, -12}, 30] (* Harvey P. Dale, Jun 25 2017 *)

Prog

(Magma) I:=[1, -1, 5, -12]; [n le 4 select I[n] else -Self(n-1)+4*Self(n-2)-3*Self(n-3)+Self(n-4): n in [1..30]]; // Vincenzo Librandi, Jun 28 2017

Crossrefs

Sequence in context: A185699 A301873 A368094 * A300534 A359189 A297909

Adjacent sequences: A077915 A077916 A077917 * A077919 A077920 A077921

Keyword

sign,easy

Author

N. J. A. Sloane, Nov 17 2002

Status

approved