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A084847 2*3^n+2^(2n-1)*(n-2). 0
1, 4, 18, 86, 418, 2022, 9650, 45334, 209730, 956870, 4312402, 19228662, 84948962, 372287398, 1620178674, 7008019670, 30150864514, 129107299206, 550530654866, 2338786731958, 9902578218786, 41802362561894, 175984622563378 (list; graph; refs; listen; history; text; internal format)
OFFSET

0,2

COMMENTS

Binomial transform of A084643. Third binomial transform of abs(A060747).

LINKS

Table of n, a(n) for n=0..22.

Index entries for linear recurrences with constant coefficients, signature (11,-40,48).

FORMULA

G.f.: (1-7x+14x^2)/((1-3x)(1-4x)^2).

CROSSREFS

Sequence in context: A030278 A318217 A151252 * A082685 A111966 A225887

Adjacent sequences:  A084844 A084845 A084846 * A084848 A084849 A084850

KEYWORD

easy,nonn

AUTHOR

Paul Barry, Jun 09 2003

STATUS

approved

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Last modified December 14 11:52 EST 2018. Contains 318097 sequences. (Running on oeis4.)