A048491 a(n) = T(8,n), array T given by A048483.

1, 10, 28, 64, 136, 280, 568, 1144, 2296, 4600, 9208, 18424, 36856, 73720, 147448, 294904, 589816, 1179640, 2359288, 4718584, 9437176, 18874360, 37748728, 75497464, 150994936, 301989880, 603979768, 1207959544, 2415919096

Offset

0,2

Comments

n-th difference of a(n), a(n-1), ..., a(0) is (9, 9, 9, ...).

Links

Table of n, a(n) for n=0..28.

Index entries for linear recurrences with constant coefficients, signature (3, -2).

Formula

a(n) = 9 * 2^n - 8. - Ralf Stephan

Equals binomial transform of [1, 9, 9, 9, ...]. - Gary W. Adamson, Apr 29 2008

a(n) = 2*a(n-1) + 8, with a(0)=1. - Vincenzo Librandi, Aug 06 2010

a(n) = 2*A053209(n), n>0. - Philippe Deléham, Apr 15 2013

a(n) = 3*a(n-1) - 2*a(n-2) with a(0)=1, a(1)=10. - Philippe Deléham, Apr 15 2013

G.f.: (1+7*x)/((1-x)*(1-2*x)). - Philippe Deléham, Apr 15 2013

Mathematica

a=1; lst={a}; k=9; Do[a+=k; AppendTo[lst, a]; k+=k, {n, 0, 5!}]; lst (* Vladimir Joseph Stephan Orlovsky, Dec 16 2008 *)
9*2^Range[0, 30]-8 (* Harvey P. Dale, May 14 2021 *)

Crossrefs

Sequence in context: A053790 A364694 A269441 * A124703 A333241 A251319

Adjacent sequences: A048488 A048489 A048490 * A048492 A048493 A048494

Keyword

nonn,easy

Author

Clark Kimberling

Status

approved