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A084643 a(n) = 3^(n-1)*(2*n-3) + 2^(n+1). 3
1, 3, 11, 43, 167, 631, 2315, 8275, 28943, 99439, 336659, 1126027, 3728279, 12239527, 39890843, 129205699, 416249375, 1334710495, 4262149667, 13560765691, 43005771431, 135988785943, 428882869931, 1349402340403 (list; graph; refs; listen; history; text; internal format)
OFFSET

0,2

COMMENTS

Binomial transform of A048495. Second binomial transform of 1, 1, 3, 5, 7, ...

LINKS

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

Index entries for linear recurrences with constant coefficients, signature (8,-21,18).

FORMULA

G.f.: (1 - 5*x + 8*x^2)/((1-2*x)*(1-3*x)^2). [Colin Barker, Mar 22 2012]

MATHEMATICA

LinearRecurrence[{8, -21, 18}, {1, 3, 11}, 30] (* Harvey P. Dale, Dec 12 2015 *)

PROG

(MAGMA) [3^(n-1)*(2*n-3)+2^(n+1) : n in [0..30]]; // Vincenzo Librandi, Sep 25 2011

(PARI) Vec((1-5*x+8*x^2)/(1-2*x)/(1-3*x)^2+O(x^99)) \\ Charles R Greathouse IV, Mar 22 2012

CROSSREFS

Cf. A060747.

Sequence in context: A034477 A140803 A246758 * A302705 A007583 A026671

Adjacent sequences:  A084640 A084641 A084642 * A084644 A084645 A084646

KEYWORD

nonn,easy

AUTHOR

Paul Barry, Jun 09 2003

STATUS

approved

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Last modified May 25 16:40 EDT 2020. Contains 334595 sequences. (Running on oeis4.)