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Expansion of g.f.: (1+x)/(1-22*x).
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%I #30 Oct 13 2022 11:38:14

%S 1,23,506,11132,244904,5387888,118533536,2607737792,57370231424,

%T 1262145091328,27767192009216,610878224202752,13439320932460544,

%U 295665060514131968,6504631331310903296,143101889288839872512,3148241564354477195264,69261314415798498295808,1523748917147566962507776

%N Expansion of g.f.: (1+x)/(1-22*x).

%H Kenny Lau, <a href="/A170742/b170742.txt">Table of n, a(n) for n = 0..744</a>

%H <a href="/index/Rec#order_01">Index entries for linear recurrences with constant coefficients</a>, signature (22).

%F a(n) = Sum_{k=0..n} A097805(n,k)*(-1)^(n-k)*23^k. - _Philippe Deléham_, Dec 04 2009

%F a(0) = 1; for n>0, a(n) = 23*22^(n-1). - _Vincenzo Librandi_, Dec 05 2009

%F E.g.f.: (23*exp(22*x) - 1)/22. - _G. C. Greubel_, Sep 25 2019

%p k:=23; seq(`if`(n=0, 1, k*(k-1)^(n-1)), n = 0..25); # _G. C. Greubel_, Sep 25 2019

%t With[{k=23}, Table[If[n==0,1, k*(k-1)^(n-1)], {n,0,25}]] (* _G. C. Greubel_, Sep 25 2019 *)

%t LinearRecurrence[{22},{1,23},20] (* _Harvey P. Dale_, Oct 13 2022 *)

%o (Python) for i in range(31):print(i,23*22**(i-1) if i>0 else 1) # _Kenny Lau_, Aug 01 2017

%o (PARI) vector(26, n, k=23; if(n==1, 1, k*(k-1)^(n-2))) \\ _G. C. Greubel_, Sep 25 2019

%o (Magma) k:=23; [1] cat [k*(k-1)^(n-1): n in [1..25]]; // _G. C. Greubel_, Sep 25 2019

%o (Sage) k=23; [1]+[k*(k-1)^(n-1) for n in (1..25)] # _G. C. Greubel_, Sep 25 2019

%o (GAP) k:=23;; Concatenation([1], List([1..25], n-> k*(k-1)^(n-1) )); # _G. C. Greubel_, Sep 25 2019

%Y Cf. A003945, A097805.

%K nonn,easy

%O 0,2

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