The OEIS is supported by the many generous donors to the OEIS Foundation.

 Hints (Greetings from The On-Line Encyclopedia of Integer Sequences!)
 A120463 Expansion of x*(1+x+2*x^3) / ( (x-1)*(1+x)*(3*x^2-1) ). 0
 0, 1, 1, 4, 6, 13, 21, 40, 66, 121, 201, 364, 606, 1093, 1821, 3280, 5466, 9841, 16401, 29524, 49206, 88573, 147621, 265720, 442866, 797161, 1328601, 2391484, 3985806, 7174453, 11957421, 21523360, 35872266, 64570081, 107616801, 193710244 (list; graph; refs; listen; history; text; internal format)
 OFFSET 0,4 COMMENTS Top element of the vector obtained by multiplying the n-th power of the 5 X 5 matrix [[0, 1, 0, 0, 0], [1, 0, 1, 0, 0], [0, 1, 0, 1, 0], [0, 0, 1, 0, 1], [0, 0, 0, 1, 0]] by the column vector [0, 1, 1, 2, 3]. LINKS Index entries for linear recurrences with constant coefficients, signature (0,4,0,-3). FORMULA a(2n+2) = A134931(n). a(2n+1) = A003462(n+1). - R. J. Mathar, Nov 07 2011 MATHEMATICA LinearRecurrence[{0, 4, 0, -3}, {0, 1, 1, 4, 6}, 40] (* Harvey P. Dale, Dec 15 2018 *) CROSSREFS Sequence in context: A013122 A012964 A284798 * A049732 A262194 A136391 Adjacent sequences:  A120460 A120461 A120462 * A120464 A120465 A120466 KEYWORD nonn,easy AUTHOR Roger L. Bagula and Gary W. Adamson, Jun 30 2006 STATUS approved

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

Last modified June 29 21:48 EDT 2022. Contains 354913 sequences. (Running on oeis4.)