cp's OEIS Frontend

This is a front-end for the Online Encyclopedia of Integer Sequences, made by Christian Perfect. The idea is to provide OEIS entries in non-ancient HTML, and then to think about how they're presented visually. The source code is on GitHub.

A141365 Expansion of (1-5x^2-7x^3-2x^4+x^6)/((1-x)(1-x^3)^2).

Original entry on oeis.org

1, 1, -4, -9, -11, -21, -31, -35, -50, -65, -71, -91, -111, -119, -144, -169, -179, -209, -239, -251, -286, -321, -335, -375, -415, -431, -476, -521, -539, -589, -639, -659, -714, -769, -791, -851, -911, -935, -1000, -1065, -1091, -1161, -1231
Offset: 0

Views

Author

Paul Barry, Jun 27 2008

Keywords

Comments

Hankel transform of A141364.

Crossrefs

Cf. A141352.

Programs

  • Mathematica
    CoefficientList[Series[(1-5x^2-7x^3-2x^4+x^6)/((1-x)(1-x^3)^2),{x,0,60}],x] (* or *) LinearRecurrence[{1,0,2,-2,0,-1,1},{1,1,-4,-9,-11,-21,-31},60] (* Harvey P. Dale, Oct 21 2013 *)

Formula

G.f.: (1-5x^2-7x^3-2x^4+x^6)/(1-x-2x^3+2x^4+x^6-x^7)
a(0)=1, a(1)=1, a(2)=-4, a(3)=-9, a(4)=-11, a(5)=-21, a(6)=-31, a(n)=a(n-1)+ 2*a(n-3)- 2*a(n-4)-a(n-6)+a (n-7). - Harvey P. Dale, Oct 21 2013