A143373 Expansion of x/(1 - x - 2*x^3 - 2*x^5 - x^7).

1, 1, 1, 3, 5, 9, 17, 30, 55, 100, 181, 330, 599, 1088, 1978, 3593, 6529, 11864, 21556, 39169, 71171, 129319, 234978, 426961, 775801, 1409655, 2561384, 4654113, 8456664, 15366012, 27920509

Offset

1,4

References

Claude Shannon and Warren Weaver, A Mathematical Theory of Communication, University of Illinois Press, Chicago, 1963, pp. 37-38.

Links

G. C. Greubel, Table of n, a(n) for n = 1..1000

Index entries for linear recurrences with constant coefficients, signature (1,0,2,0,2,0,1).

Mathematica

Rest@CoefficientList[Series[x/(1 -x -2*x^3 -2*x^5 -x^7), {x, 0, 40}], x]

Prog

(PARI) my(x='x+O('x^40)); Vec(x/(1-x-2*x^3-2*x^5-x^7)) \\ G. C. Greubel, Sep 27 2017
(Sage)
def A143373_list(prec):
    P.<x> = PowerSeriesRing(ZZ, prec)
    return P( x/(1 -x -2*x^3 -2*x^5 -x^7) ).list()
a=A143373_list(40); a[1:] # G. C. Greubel, Feb 08 2021
(Magma)
R<x>:=PowerSeriesRing(Rationals(), 40);
Coefficients(R!( x/(1 -x -2*x^3 -2*x^5 -x^7) )); // G. C. Greubel, Feb 08 2021

Crossrefs

Cf. A122762, A143351, A143372, A143375.

Sequence in context: A288232 A289261 A357549 * A282184 A102475 A066173

Adjacent sequences: A143370 A143371 A143372 * A143374 A143375 A143376

Keyword

nonn,easy

Author

Roger L. Bagula and Gary W. Adamson, Oct 22 2008

Extensions

Edited by G. C. Greubel, Feb 08 2021

Status

approved