A113440 First row of A113439.

1, 2, 8, 34, 146, 627, 2689, 11521, 49337, 211233, 904306, 3871305, 16572812, 70947073, 303719624, 1300203634, 5566087073, 23828058969, 102006385362, 436682772844, 1869410868456, 8002827727921, 34259590954322

Offset

0,2

Links

G. C. Greubel, Table of n, a(n) for n = 0..1000

Index entries for linear recurrences with constant coefficients, signature (9,-28,38,-20,1).

Formula

a(n) = A113439(4*n).

a(n) = 9*a(n-1) - 28*a(n-2) + 38*a(n-3) - 20*a(n-4) + a(n-5).

G.f.: -(1-7*x+18*x^2-20*x^3+8*x^4)/(-1+9*x-28*x^2+38*x^3-20*x^4+x^5).

Mathematica

CoefficientList[Series[-(1 - 7*x + 18*x^2 - 20*x^3 + 8*x^4)/(-1 + 9*x - 28*x^2 + 38*x^3 - 20*x^4 + x^5), {x, 0, 50}], x] (* G. C. Greubel, Mar 11 2017 *)
LinearRecurrence[{9, -28, 38, -20, 1}, {1, 2, 8, 34, 146}, 30] (* Harvey P. Dale, Jul 20 2024 *)

Prog

(PARI) x='x+O('x^50); Vec(-(1-7*x+18*x^2-20*x^3+8*x^4)/(-1+9*x-28*x^2+38*x^3-20*x^4+x^5)) \\ G. C. Greubel, Mar 11 2017

Crossrefs

Cf. A113439.

Sequence in context: A228655 A192402 A014445 * A296227 A034999 A067336

Adjacent sequences: A113437 A113438 A113439 * A113441 A113442 A113443

Keyword

nonn,easy

Author

Floor van Lamoen, Nov 04 2005

Status

approved