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A190980 a(n) = 9*a(n-1) - 3*a(n-2), with a(0)=0, a(1)=1. 4

%I #28 Dec 23 2023 09:43:09

%S 0,1,9,78,675,5841,50544,437373,3784725,32750406,283399479,2452344093,

%T 21220898400,183631053321,1589016784689,13750257902238,

%U 118985270766075,1029616663187961,8909594156393424,77097497417976933,667148694292612125,5773045756379578326

%N a(n) = 9*a(n-1) - 3*a(n-2), with a(0)=0, a(1)=1.

%H Vincenzo Librandi, <a href="/A190980/b190980.txt">Table of n, a(n) for n = 0..500</a>

%H <a href="/index/Rec#order_02">Index entries for linear recurrences with constant coefficients</a>, signature (9,-3).

%F G.f.: x/(1-9*x+3*x^2). - _Philippe Deléham_, Oct 12 2011

%t LinearRecurrence[{9,-3}, {0,1}, 50]

%t CoefficientList[Series[x/(1-9*x+3*x^2), {x,0,50}], x] (* _G. C. Greubel_, Jan 14 2018 *)

%o (PARI) x='x+O('x^30); concat([0], Vec(x/(1-9*x+3*x^2))) \\ _G. C. Greubel_, Jan 14 2018

%o (Magma) I:=[0,1]; [n le 2 select I[n] else 9*Self(n-1) - 3*Self(n-2): n in [1..30]]; // _G. C. Greubel_, Jan 14 2018

%Y Cf. A190958 (index to generalized Fibonacci sequences).

%K nonn

%O 0,3

%A _Vladimir Joseph Stephan Orlovsky_, May 24 2011

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Last modified April 25 12:33 EDT 2024. Contains 371969 sequences. (Running on oeis4.)