A180488 Partial sums of A006864.

0, 1, 3, 9, 23, 60, 152, 388, 984, 2501, 6347, 16117, 40911, 103864, 263664, 669352, 1699216, 4313673, 10950739, 27799745, 70572839, 179157364, 454811656, 1154592108, 2931065640, 7440849549, 18889457819, 47953075565

Offset: 1

Author

Jonathan Vos Post, Sep 07 2010

Keywords

• nonn
• easy

Links

• Index entries for linear recurrences with constant coefficients, signature (3,0,-4,3,-1).

Crossrefs

Cf. A006864.

Formula

a(n) = +3*a(n-1) -4*a(n-3) +3*a(n-4) -a(n-5). G.f.: x^2 / ( (x-1)*(x^4-2*x^3+2*x^2+2*x-1) ). [R. J. Mathar, Sep 19 2010]

Extensions

Edited (changed definition, deleted incorrect terms) by N. J. A. Sloane, Sep 09 2010