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A107458 G.f.: (1-x^2-x^3)/( (1+x)(1-x-x^3) ). 5
1, 0, 0, 0, 1, 0, 1, 1, 2, 2, 4, 5, 8, 11, 17, 24, 36, 52, 77, 112, 165, 241, 354, 518, 760, 1113, 1632, 2391, 3505, 5136, 7528, 11032, 16169, 23696, 34729, 50897, 74594, 109322, 160220, 234813, 344136, 504355, 739169, 1083304, 1587660, 2326828, 3410133, 4997792, 7324621 (list; graph; refs; listen; history; text; internal format)
OFFSET

0,9

COMMENTS

The sequence can be interpreted as the top-left entry of the n-th power of a 4X4 (0,1) matrix. There are 12 different choices (out of 2^16) for that (0,1) matrix. - R. J. Mathar, Mar 19 2014

LINKS

Reinhard Zumkeller, Table of n, a(n) for n = 0..1000

C. Kenneth Fan, Structure of a Hecke algebra quotient, J. Amer. Math. Soc. 10 (1997), no. 1, 139-167. [Page 156, f^2_n.]

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

FORMULA

a(0)=1, a(1)=0, a(2)=0, a(3)=0, a(n)=a(n-2)+a(n-3)+a(n-4). - Harvey P. Dale, Jun 20 2011

a(n) + a(n-1) = A000930(n-4). - R. J. Mathar, Mar 19 2014

MATHEMATICA

CoefficientList[Series[(-1+x^2+x^3)/(-1+x^2+x^3+x^4), {x, 0, 50}], x] (* or *) LinearRecurrence[{0, 1, 1, 1}, {1, 0, 0, 0}, 50] (* Harvey P. Dale, Jun 20 2011 *)

PROG

(Haskell)

a107458 n = a107458_list !! n

a107458_list = 1 : 0 : 0 : 0 : zipWith (+) a107458_list

   (zipWith (+) (tail a107458_list) (drop 2 a107458_list))

-- Reinhard Zumkeller, Mar 23 2012

(PARI) x='x+O('x^50); Vec((1-x^2-x^3)/((1+x)*(1-x-x^3))) \\ G. C. Greubel, Apr 27 2017

CROSSREFS

Cf. A013979, A135851, A078012, A001634.

Sequence in context: A240734 A238478 A013979 * A274142 A060280 A006206

Adjacent sequences:  A107455 A107456 A107457 * A107459 A107460 A107461

KEYWORD

nonn,easy

AUTHOR

N. J. A. Sloane, Mar 08 2008

STATUS

approved

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Last modified August 20 23:34 EDT 2017. Contains 290855 sequences.