login
The OEIS Foundation is supported by donations from users of the OEIS and by a grant from the Simons Foundation.

 

Logo


Hints
(Greetings from The On-Line Encyclopedia of Integer Sequences!)
A158762 Expansion of (1+9*x+80*x^2)/(1-x^2-729*x^3). 0
1, 9, 81, 738, 6642, 59787, 544644, 4901805, 44129367, 401947281, 3617545212, 32572255824, 296637113061, 2669762715372, 24041811608757, 218918218136841, 1970298831114945, 17745398880920694, 161561679852872034 (list; graph; refs; listen; history; text; internal format)
OFFSET

0,2

COMMENTS

This can be generated by multiplying the sum of the elements in the top row of the n-th power of the matrix [(0,3,0), (0,0,3),(3,1/27,0)] by 3^n.

LINKS

Table of n, a(n) for n=0..18.

Index entries for linear recurrences with constant coefficients, signature (0,1,729).

FORMULA

a(n)=a(n-2)+729*a(n-3). [From R. J. Mathar, Mar 26 2009]

MATHEMATICA

Clear[M, v, t, n];

M = {{0, t, 0}, {0, 0, t}, {t, 1/t^3, 0}};

v[0] = {1, 1, 1};

v[n_] := v[n] = M.v[n - 1];

CharacteristicPolynomial[M, x];

t = 3;

a = Table[t^n*v[n][[1]], {n, 0, 30}]

CROSSREFS

Sequence in context: A047901 A061587 A033145 * A101601 A233737 A344298

Adjacent sequences:  A158759 A158760 A158761 * A158763 A158764 A158765

KEYWORD

nonn

AUTHOR

Roger L. Bagula, Mar 25 2009

STATUS

approved

Lookup | Welcome | Wiki | Register | Music | Plot 2 | Demos | Index | Browse | More | WebCam
Contribute new seq. or comment | Format | Style Sheet | Transforms | Superseeker | Recent
The OEIS Community | Maintained by The OEIS Foundation Inc.

License Agreements, Terms of Use, Privacy Policy. .

Last modified June 16 19:49 EDT 2021. Contains 345068 sequences. (Running on oeis4.)