A083085 a(n) = (2+(-5)^n)/3.

1, -1, 9, -41, 209, -1041, 5209, -26041, 130209, -651041, 3255209, -16276041, 81380209, -406901041, 2034505209, -10172526041, 50862630209, -254313151041, 1271565755209, -6357828776041, 31789143880209, -158945719401041, 794728597005209, -3973642985026041

Offset

0,3

Comments

Inverse binomial transform of A083086.

Links

Vincenzo Librandi, Table of n, a(n) for n = 0..300

Index entries for linear recurrences with constant coefficients, signature (-4,5).

Formula

a(n) = (2+(-5)^n)/3.

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

E.g.f.: (2*exp(x)+exp(-5*x))/3.

a(n) = -5*a(n-1) + 4. - Vincenzo Librandi, Nov 12 2011

Maple

A083085:=n->(2+(-5)^n)/3: seq(A083085(n), n=0..30); # Wesley Ivan Hurt, Nov 02 2014

Mathematica

Table[(2 + (-5)^n)/3, {n, 0, 30}] (* Wesley Ivan Hurt, Nov 02 2014 *)

Prog

(Magma) [(2+(-5)^n)/3: n in [0..30]]; // Vincenzo Librandi, Nov 12 2011

Crossrefs

Cf. A083086.

Sequence in context: A183916 A199311 A146239 * A147283 A171422 A129793

Adjacent sequences: A083082 A083083 A083084 * A083086 A083087 A083088

Keyword

easy,sign

Author

Paul Barry, Apr 23 2003

Status

approved