A138034 - OEIS

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A138034

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

11

1, 1, 3, 2, -1, -3, -2, 1, 3, 2, -1, -3, -2, 1, 3, 2, -1, -3, -2, 1, 3, 2, -1, -3, -2, 1, 3, 2, -1, -3, -2, 1, 3, 2, -1, -3, -2, 1, 3, 2, -1, -3, -2, 1, 3, 2, -1, -3, -2, 1, 3, 2, -1, -3, -2, 1, 3, 2, -1, -3, -2, 1, 3, 2, -1, -3, -2, 1, 3, 2, -1, -3, -2, 1, 3, 2, -1, -3, -2, 1, 3, 2, -1, -3, -2, 1, 3, 2, -1, -3, -2, 1, 3, 2, -1, -3, -2, 1, 3, 2, -1, -3, -2, 1, 3

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OFFSET

0,3

COMMENTS

Essentially a duplicate of A119910: 1, followed by A119910. - Joerg Arndt, Nov 14 2014

LINKS

Table of n, a(n) for n=0..104.

Karem Boubaker and Lin Zhang, Fermat-linked relations for the Boubaker polynomial sequences via Riordan matrices analysis, arXiv preprint arXiv:1203.2082, 2012. - From N. J. A. Sloane, Sep 15 2012

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

FORMULA

a(n) = A119910(n), n>=1.

G.f.: (1+3*x^2)/(1-x+x^2). a(n)=a(n-1)-a(n-2), n>2.

MATHEMATICA

CoefficientList[Series[(1 + 3*x^2)/(1 - x + x^2), {x, 0, 100}], x] (* Wesley Ivan Hurt, Jan 15 2017 *)

LinearRecurrence[{1, -1}, {1, 1, 3}, 120] (* Harvey P. Dale, Jun 14 2024 *)

CROSSREFS

Cf. A135929, A135936, A137276.

Sequence in context: A280048 A119910 A130784 * A229216 A087818 A112746

Adjacent sequences: A138031 A138032 A138033 * A138035 A138036 A138037

KEYWORD

sign,easy

AUTHOR

Karem Boubaker (mmbb11112000(AT)yahoo.fr), Mar 01 2008; corrected Mar 03 2008

STATUS

approved