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A153972 a(n) = 2^n + 6. 7
7, 8, 10, 14, 22, 38, 70, 134, 262, 518, 1030, 2054, 4102, 8198, 16390, 32774, 65542, 131078, 262150, 524294, 1048582, 2097158, 4194310, 8388614, 16777222, 33554438, 67108870, 134217734, 268435462, 536870918, 1073741830, 2147483654 (list; graph; refs; listen; history; text; internal format)
OFFSET

0,1

COMMENTS

Old name was "a(n+1) = 2*(a(n) - 2) - 2, a(0) = 7".

LINKS

Vincenzo Librandi, Table of n, a(n) for n = 0..1000

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

FORMULA

a(n+1) = A209724(2*n-1). - L. Edson Jeffery, Nov 28 2012

From Vincenzo Librandi, May 13 2014: (Start)

G.f.: (7 - 13*x)/((1-x)*(1-2*x)).

a(n) = 2^n + 6

a(n) = 3*a(n-1) - 2*a(n-2). (End)

E.g.f.: exp(2*x) + 6. - G. C. Greubel, Sep 01 2016

MATHEMATICA

a=7; lst={a}; Do[a=(a-2)*2-2; AppendTo[lst, a], {n, 30}]; lst

NestList[ 2# - 6 &, 7, 31] (* Robert G. Wilson v, Nov 28 2012 *)

CoefficientList[Series[(7 - 13 x)/((1 - x) (1 - 2 x)), {x, 0, 30}], x] (* Vincenzo Librandi, May 13 2014 *)

LinearRecurrence[{3, -2}, {7, 8}, 25] (* G. C. Greubel, Sep 01 2016 *)

PROG

(MAGMA) [2^n+6: n in [0..40]]; // Vincenzo Librandi, May 13 2014

(PARI) a(n)=2^n+6 \\ Charles R Greathouse IV, Oct 07 2015

CROSSREFS

Cf. A209724.

Sequence in context: A048588 A141676 A127164 * A286420 A111064 A071117

Adjacent sequences:  A153969 A153970 A153971 * A153973 A153974 A153975

KEYWORD

nonn,easy

AUTHOR

Vladimir Joseph Stephan Orlovsky, Jan 03 2009

STATUS

approved

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Last modified June 20 09:12 EDT 2019. Contains 324234 sequences. (Running on oeis4.)