A115052 Expansion of 1/(3*x^2 - 3*x + 1)^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

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