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A083086 (2*2^n+(-4)^n)/3. 4
1, 0, 8, -16, 96, -320, 1408, -5376, 22016, -87040, 350208, -1396736, 5595136, -22364160, 89489408, -357892096, 1431699456, -5726535680, 22906667008, -91625619456, 366504574976, -1466014105600, 5864064811008, -23456242466816, 93825003421696, -375299946577920 (list; graph; refs; listen; history; text; internal format)
OFFSET

0,3

COMMENTS

Binomial transform of A083085

LINKS

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

Index to sequences with linear recurrences with constant coefficients, signature (-2,8).

FORMULA

a(n)=(2*2^n+(-4)^n)/3.

G.f. (1+2*x)/((1+4*x)*(1-2*x).

E.g.f. (2*exp(2*x)+exp(-4*x))/3.

a(n)=(-1)^n*A000079(n)*A078008 - Paul Barry, Feb 12 2004

a(n) = -2*a(n-1)+8*a(n-2). - Vincenzo Librandi, Nov 12 2011

PROG

(MAGMA) [(2*2^n+(-4)^n)/3: n in [0..30]]; // Vincenzo Librandi, Nov 12 2011

CROSSREFS

Cf. A083216.

Sequence in context: A131539 A117868 A062508 * A230930 A080452 A107906

Adjacent sequences:  A083083 A083084 A083085 * A083087 A083088 A083089

KEYWORD

sign,easy

AUTHOR

Paul Barry, Apr 23 2003

STATUS

approved

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Last modified April 17 06:50 EDT 2014. Contains 240634 sequences.