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A020447 Expansion of 1/((1-5x)(1-8x)(1-11x)). 1
1, 24, 393, 5480, 70161, 853944, 10066393, 116192520, 1322205921, 14898923864, 166735197993, 1856912289960, 20608880226481, 228161663489784, 2521496249891193, 27830232878409800, 306882907287251841 (list; graph; refs; listen; history; text; internal format)
OFFSET

0,2

LINKS

Vincenzo Librandi, Table of n, a(n) for n = 0..200

Index entries for linear recurrences with constant coefficients, signature (24,-183,440).

FORMULA

a(n) = 25*5^n/18 -64*8^n/9 +121*11^n/18. - R. J. Mathar, Jun 29 2013

a(0)=1, a(1)=24, a(2)=393; for n>2, a(n) = 24*a(n-1) -183*a(n-2) +440*a(n-3). - Vincenzo Librandi, Jul 03 2013

a(n) = 19*a(n-1) -88*a(n-2) +5^n. - Vincenzo Librandi, Jul 03 2013

MATHEMATICA

CoefficientList[Series[1 / ((1 - 5 x) (1 - 8 x) (1 - 11 x)), {x, 0, 20}], x] (* Vincenzo Librandi, Jul 03 2013 *)

LinearRecurrence[{24, -183, 440}, {1, 24, 393}, 30] (* Harvey P. Dale, Jun 20 2015 *)

PROG

(MAGMA) m:=20; R<x>:=PowerSeriesRing(Integers(), m); Coefficients(R!(1/((1-5*x)*(1-8*x)*(1-11*x)))); /* or */ I:=[1, 24, 393]; [n le 3 select I[n] else 24*Self(n-1)-183*Self(n-2)+440*Self(n-3): n in [1..20]]; // Vincenzo Librandi, Jul 03 2013

CROSSREFS

Sequence in context: A025947 A007752 A145602 * A021894 A021694 A019687

Adjacent sequences:  A020444 A020445 A020446 * A020448 A020449 A020450

KEYWORD

nonn,easy

AUTHOR

N. J. A. Sloane.

STATUS

approved

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Last modified July 13 13:48 EDT 2020. Contains 335688 sequences. (Running on oeis4.)