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A165231 a(0)=1, a(1)=8, a(n)=16*a(n-1)-8*a(n-2) for n>1 . 1
1, 8, 120, 1856, 28736, 444928, 6888960, 106663936, 1651511296, 25570869248, 395921817600, 6130182127616, 94915539501056, 1469607174995968, 22754390483927040, 352313390342864896, 5454979121614422016 (list; graph; refs; listen; history; text; internal format)
OFFSET

0,2

LINKS

Table of n, a(n) for n=0..16.

Index entries for linear recurrences with constant coefficients, signature (16, -8).

FORMULA

G.f.: (1-8*x)/(1-16*x+8x^2) .

a(n) = (1/2)*((8+2*sqrt(14))^n+(8-2*sqrt(14))^n), n>=0 [From Paolo P. Lava, Sep 16 2009]

MATHEMATICA

LinearRecurrence[{16, -8}, {1, 8}, 30] (* or *) Simplify[With[{c1=Sqrt[14], c2=2Sqrt[14]}, Table[(15(8-c2)^n+4c1 (8-c2)^n+(8+c2)^n)/(4(4+c1)), {n, 30}]]] (* Harvey P. Dale, Jul 04 2011 *)

CROSSREFS

Sequence in context: A053129 A249641 A045899 * A004381 A166179 A130979

Adjacent sequences:  A165228 A165229 A165230 * A165232 A165233 A165234

KEYWORD

nonn

AUTHOR

Philippe Deléham, Sep 09 2009

STATUS

approved

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Last modified April 5 06:13 EDT 2020. Contains 333238 sequences. (Running on oeis4.)