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Expansion of g.f.: (1+x)/(1-28*x).
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%I #27 Sep 08 2022 08:45:49

%S 1,29,812,22736,636608,17825024,499100672,13974818816,391294926848,

%T 10956257951744,306775222648832,8589706234167296,240511774556684288,

%U 6734329687587160064,188561231252440481792,5279714475068333490176,147832005301913337724928

%N Expansion of g.f.: (1+x)/(1-28*x).

%H Kenny Lau, <a href="/A170748/b170748.txt">Table of n, a(n) for n = 0..690</a>

%H <a href="/index/Rec#order_01">Index entries for linear recurrences with constant coefficients</a>, signature (28).

%F a(n) = Sum_{k=0..n} A097805(n,k)*(-1)^(n-k)*29^k. - _Philippe Deléham_, Dec 04 2009

%F a(0) = 1; for n>0, a(n) = 29*28^(n-1). - _Vincenzo Librandi_, Dec 05 2009

%F E.g.f.: (29*exp(28*x) -1)/28. - _G. C. Greubel_, Sep 25 2019

%p k:=29; seq(`if`(n=0, 1, k*(k-1)^(n-1)), n = 0..25); # _G. C. Greubel_, Sep 25 2019

%t Join[{1},Table[29*28^(n-1),{n,20}]] (* or *) Join[{1}, NestList[28#&, 29, 20]] (* _Harvey P. Dale_, Feb 05 2012 *)

%o (Python) for i in range(31):print(i,29*28**(i-1) if i>0 else 1) # _Kenny Lau_, Aug 03 2017

%o (PARI) vector(26, n, k=29; if(n==1, 1, k*(k-1)^(n-2))) \\ _G. C. Greubel_, Sep 25 2019

%o (Magma) k:=29; [1] cat [k*(k-1)^(n-1): n in [1..25]]; // _G. C. Greubel_, Sep 25 2019

%o (Sage) k=29; [1]+[k*(k-1)^(n-1) for n in (1..25)] # _G. C. Greubel_, Sep 25 2019

%o (GAP) k:=29;; 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