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A115052 Expansion of 1/(3*x^2 - 3*x + 1)^2. 2
1, 6, 21, 54, 108, 162, 135, -162, -1053, -2916, -5832, -8748, -8019, 4374, 41553, 118098, 236196, 354294, 334611, -118098, -1476225, -4251528, -8503056, -12754584, -12223143, 3188646, 49424013, 143489070, 286978140 (list; graph; refs; listen; history; text; internal format)
OFFSET

0,2

COMMENTS

q=1 coefficient expansion of hierarchical lattice renormalization polynomial.

REFERENCES

The Beauty of Fractals, Springer-Verlag, New York, 1986, editors Peitgen and Richter, p. 146

LINKS

Vincenzo Librandi, Table of n, a(n) for n = 0..200

Index entries for linear recurrences with constant coefficients, signature (6,-15,18,-9).

MAPLE

A115052 := proc(n) 1/(3*x^2-3*x+1)^2 ; coeftayl(%, x=0, n) ; end proc:# R. J. Mathar, Sep 17 2011

PROG

(MAGMA) I:=[1, 6, 21, 54]; [n le 4 select I[n] else 6*Self(n-1)-15*Self(n-2)+18*Self(n-3)-9*Self(n-4): n in [1..40]]; // Vincenzo Librandi, Sep 20 2011

CROSSREFS

Autoconvolution of A057083.

Sequence in context: A069778 A015644 A067680 * A025203 A262719 A238702

Adjacent sequences:  A115049 A115050 A115051 * A115053 A115054 A115055

KEYWORD

sign,easy

AUTHOR

Roger L. Bagula, Feb 28 2006

STATUS

approved

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Last modified January 26 20:33 EST 2020. Contains 331288 sequences. (Running on oeis4.)