A155603 a(n) = 5^n+3^n-1.

1, 7, 33, 151, 705, 3367, 16353, 80311, 397185, 1972807, 9824673, 49005271, 244672065, 1222297447, 6108298593, 30531927031, 152630937345, 763068593287, 3815084686113, 19074648589591, 95370918425025, 476847618556327

Offset

0,2

Links

Table of n, a(n) for n=0..21.

Index entries for linear recurrences with constant coefficients, signature (9,-23,15).

Formula

G.f.: 1/(1-5*x)+1/(1-3*x)-1/(1-x).

E.g.f.: e^(5*x)+e^(3*x)-e^x.

a(n) = 8*a(n-1)-15*a(n-2)-8 with a(0)=1, a(1)=7. - Vincenzo Librandi, Jul 21 2010

a(n) = A074606(n)-1. - R. J. Mathar, Mar 10 2022

Mathematica

Table[5^n+3^n-1, {n, 0, 30}] (* or *) LinearRecurrence[{9, -23, 15}, {1, 7, 33}, 30] (* Harvey P. Dale, Oct 14 2020 *)

Prog

(PARI) a(n)=5^n+3^n-1 \\ Charles R Greathouse IV, Jun 11 2015

Crossrefs

Cf. A074501, A020515, A155588, A155590, A155592, A155593, A155594, A155596, A155597, A155598, A155599, A155600, A155601, A155602.

Sequence in context: A211829 A227555 A304278 * A282991 A344816 A295270

Adjacent sequences: A155600 A155601 A155602 * A155604 A155605 A155606

Keyword

nonn,easy

Author

Mohammad K. Azarian, Jan 25 2009

Status

approved