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Expansion of 1/((1-3x)(1-5x)(1-10x)).
1

%I #20 Aug 12 2023 17:12:13

%S 1,18,229,2562,27061,278058,2818549,28377522,284741941,2852272698,

%T 28547052469,285592329282,2856532847221,28568377838538,

%U 285699029999989,2857066572421842,28571047129374901,285712378448671578

%N Expansion of 1/((1-3x)(1-5x)(1-10x)).

%H Vincenzo Librandi, <a href="/A017916/b017916.txt">Table of n, a(n) for n = 0..200</a>

%H <a href="/index/Rec">Index entries for linear recurrences with constant coefficients</a>, signature (18,-95,150).

%F a(0)=1, a(2)=18, a(3)=229, a(n) = 18*a(n-1)-95*a(n-2)+150*a(n-3). - _Vincenzo Librandi_, Jul 01 2013

%F a(n) = 15*a(n-1) -50*a(n-2) -3^n. - _Vincenzo Librandi_, Jul 01 2013

%F a(n) = (2*10^(n+2) - 7*5^(n+2) + 5*3^(n+2))/70. [_Yahia Kahloune_, Aug 13 2013]

%p a:= n-> (Matrix(3, (i, j)-> `if`(i=j-1, 1, `if`(j=1, [18, -95, 150][i], 0)))^n)[1, 1]: seq(a(n), n=0..25); # _Alois P. Heinz_, Jul 01 2013

%t CoefficientList[Series[1 / ((1 - 3 x) (1 - 5 x) (1 - 10 x)), {x, 0, 30}], x] (* _Vincenzo Librandi_, Jul 01 2013 *)

%t LinearRecurrence[{18,-95,150},{1,18,229},20] (* _Harvey P. Dale_, Aug 12 2023 *)

%o (Magma) I:=[1, 18, 229]; [n le 3 select I[n] else 18*Self(n-1)-95*Self(n-2)+150*Self(n-3): n in [1..20]]; /* or */ m:=20; R<x>:=PowerSeriesRing(Integers(), m); Coefficients(R!(1/((1-3*x)*(1-5*x)*(1-10*x)))); // _Vincenzo Librandi_, Jul 01 2013

%o (PARI) a(n) = (2*10^(n+2) - 7*5^(n+2) + 5*3^(n+2))/70; \\ _Joerg Arndt_, Aug 13 2013

%K nonn,easy

%O 0,2

%A _N. J. A. Sloane_.