A165326 a(0)=a(1)=1, a(n) = -a(n-1) for n > 1.

1, 1, -1, 1, -1, 1, -1, 1, -1, 1, -1, 1, -1, 1, -1, 1, -1, 1, -1, 1, -1, 1, -1, 1, -1, 1, -1, 1, -1, 1, -1, 1, -1, 1, -1, 1, -1, 1, -1, 1, -1, 1, -1, 1, -1, 1, -1, 1, -1, 1, -1, 1, -1, 1, -1, 1, -1, 1, -1, 1, -1, 1, -1, 1, -1, 1, -1, 1, -1, 1, -1, 1, -1, 1, -1, 1, -1, 1, -1, 1, -1, 1, -1, 1

Offset

0,1

Comments

Inverse binomial transform of A040000(n) = 1,2,2,2,2,...; binomial transform of (-1)^(n+1)*A000918(n) = 1,0,-2,6,-14,30,-62,... - Philippe Deléham, Sep 16 2009

This is also the Z-sequence of the Riordan triangle A105809. See the W. Lang link under A006232 for Riordan A- and Z-sequences. - Wolfdieter Lang, Oct 04 2014

Links

Table of n, a(n) for n=0..83.

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

Formula

G.f.: (1+2*x)/(1+x).

E.g.f.: 2-exp(-x).

a(n) = -a(n-1). - Wesley Ivan Hurt, Apr 23 2021

Mathematica

PadRight[{1}, 120, {-1, 1}] (* Harvey P. Dale, Dec 04 2012 *)
Join[{1}, LinearRecurrence[{-1}, {1}, 83]] (* Ray Chandler, Aug 12 2015 *)

Crossrefs

Cf. A033999.

Sequence in context: A174351 A339265 A181432 * A143621 A292117 A098417

Adjacent sequences: A165323 A165324 A165325 * A165327 A165328 A165329

Keyword

easy,sign,mult

Author

Philippe Deléham, Sep 14 2009

Status

approved