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A018912 Expansion of 1/((1-4x)(1-5x)(1-10x)). 2
1, 19, 251, 2879, 30891, 320439, 3266131, 32986399, 331554971, 3324266759, 33287301411, 333100377519, 3332157369451, 33327408774679, 333303531583091, 3333183608754239, 33332581847126331, 333329564449052199 (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 (19,-110,200).

FORMULA

a(n) = 8*4^n/3 -5*5^n/1 +10*10^n/3. - R. J. Mathar, Jun 29 2013

a(0)=1, a(1)=19, a(2)=251; for n>2, a(n) = 19*a(n-1) -110*a(n-2) +200*a(n-3). - Vincenzo Librandi, Jul 02 2013

a(n) = 15*a(n-1) -50*a(n-2) +4^n. - Vincenzo Librandi, Jul 02 2013

MATHEMATICA

CoefficientList[Series[1 / ((1 - 4 x) (1 - 5 x) (1 - 10 x)), {x, 0, 20}], x] (* Vincenzo Librandi, Jul 02 2012 *)

PROG

(MAGMA) m:=20; R<x>:=PowerSeriesRing(Integers(), m); Coefficients(R!(1/((1-4*x)*(1-5*x)*(1-10*x)))); /* or */ I:=[1, 19, 251]; [n le 3 select I[n] else 19*Self(n-1)-110*Self(n-2)+200*Self(n-3): n in [1..20]]; // Vincenzo Librandi, Jul 02 2013

CROSSREFS

Sequence in context: A021229 A021464 A017998 * A021202 A125454 A293917

Adjacent sequences:  A018909 A018910 A018911 * A018913 A018914 A018915

KEYWORD

nonn,easy

AUTHOR

N. J. A. Sloane.

STATUS

approved

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Last modified November 11 15:51 EST 2019. Contains 329019 sequences. (Running on oeis4.)