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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 (list; graph; refs; listen; history; text; internal format)
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.

a(n) = 3*(C(2*n,n) mod 2) + (1/6)*(-(n mod 6) + 2*((n+1) mod 6) + 3*((n+2) mod 6) + ((n+3) mod 6) - 2*((n+4) mod 6) - 3*((n+5) mod 6)), with n>=0. - Paolo P. Lava, Mar 18 2008

MATHEMATICA

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

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

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Last modified November 23 20:23 EST 2017. Contains 295141 sequences.