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Expansion of g.f.: (1+x)/(1-43*x).
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%I #27 Sep 08 2022 08:45:49

%S 1,44,1892,81356,3498308,150427244,6468371492,278139974156,

%T 11960018888708,514280812214444,22114074925221092,950905221784506956,

%U 40888924536733799108,1758223755079553361644,75603621468420794550692,3250955723142094165679756

%N Expansion of g.f.: (1+x)/(1-43*x).

%H Vincenzo Librandi, <a href="/A170763/b170763.txt">Table of n, a(n) for n = 0..600</a>

%H <a href="/index/Rec#order_01">Index entries for linear recurrences with constant coefficients</a>, signature (43).

%F a(n) = Sum_{k=0..n} A097805(n,k)*(-1)^(n-k)*44^k. - _Philippe Deléham_, Dec 04 2009

%F a(0) = 1; for n>0, a(n) = 44*43^(n-1). - _Vincenzo Librandi_, Dec 05 2009

%F a(0)=1, a(1)=44, a(n) = 43*a(n-1). - _Vincenzo Librandi_, Dec 11 2012

%F E.g.f.: (44*exp(43*x) - 1)/43. - _G. C. Greubel_, Oct 10 2019

%p k:=44; seq(`if`(n=0, 1, k*(k-1)^(n-1)), n = 0..25); # _G. C. Greubel_, Oct 10 2019

%t CoefficientList[Series[(1+x)/(1-43*x), {x, 0, 20}], x] (* _Vincenzo Librandi_, Dec 09 2012 *)

%t Join[{1},NestList[43#&,44,20]] (* _Harvey P. Dale_, Jan 15 2013 *)

%t With[{k = 44}, Table[If[n==0, 1, k*(k-1)^(n-1)], {n, 0, 25}]] (* _G. C. Greubel_, Oct 10 2019 *)

%o (Magma) [1] cat [44*43^(n-1): n in [1..20]]; // _Vincenzo Librandi_, Dec 11 2012

%o (PARI) a(n)=44*43^n\43 \\ _Charles R Greathouse IV_, Jul 01 2013

%o (Sage) k=44; [1]+[k*(k-1)^(n-1) for n in (1..25)] # _G. C. Greubel_, Oct 10 2019

%o (GAP) k:=44;; Concatenation([1], List([1..25], n-> k*(k-1)^(n-1) )); # _G. C. Greubel_, Oct 10 2019

%Y Cf. A003945.

%K nonn,easy

%O 0,2

%A _N. J. A. Sloane_, Dec 04 2009