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A099841 Expansion of (1-16*x)/(1-20*x+80*x^2). 0
1, 4, 0, -320, -6400, -102400, -1536000, -22528000, -327680000, -4751360000, -68812800000, -996147200000, -14417920000000, -208666624000000, -3019898880000000, -43704647680000000, -632501043200000000, -9153649049600000000, -132472897536000000000 (list; graph; refs; listen; history; text; internal format)
OFFSET

0,2

COMMENTS

Tenth binomial transform of A099839. Fifteenth binomial transform of A099840.

LINKS

Table of n, a(n) for n=0..18.

Index entries for linear recurrences with constant coefficients, signature (20,-80).

FORMULA

G.f.: (1-16*x)/(1-20*x+80*x^2).

a(n) = (10 - 2*sqrt(5))^n*(1/2 + 3*sqrt(5)/10) + (10 + 2*sqrt(5))^n*(1/2 - 3*sqrt(5)/10).

a(n) = 20*a(n-1) - 80*a(n-2); a(0)=1, a(1)=4. - Harvey P. Dale, Jun 04 2013

MATHEMATICA

CoefficientList[Series[(1-16x)/(1-20x+80x^2), {x, 0, 30}], x] (* or *) LinearRecurrence[{20, -80}, {1, 4}, 30] (* Harvey P. Dale, Jun 04 2013 *)

CROSSREFS

Cf. A099839, A099840.

Sequence in context: A119010 A255018 A176050 * A013452 A013453 A012688

Adjacent sequences:  A099838 A099839 A099840 * A099842 A099843 A099844

KEYWORD

easy,sign

AUTHOR

Paul Barry, Oct 27 2004

STATUS

approved

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Last modified November 12 04:21 EST 2019. Contains 329051 sequences. (Running on oeis4.)