A199761 - OEIS

%I #14 Mar 13 2024 19:54:36

%S 2,20,218,2396,26354,289892,3188810,35076908,385845986,4244305844,

%T 46687364282,513561007100,5649171078098,62140881859076,

%U 683549700449834,7519046704948172,82709513754429890,909804651298728788,10007851164286016666

%N (9*11^n+1)/5.

%H Vincenzo Librandi, <a href="/A199761/b199761.txt">Table of n, a(n) for n = 0..900</a>

%H <a href="/index/Rec#order_02">Index entries for linear recurrences with constant coefficients</a>, signature (12,-11).

%F a(n) = 11*a(n-1)-2.

%F a(n) = 12*a(n-1)-11*a(n-2).

%F G.f.: 2*(1-2*x)/((1-x)*(1-11*x)).

%t (9*11^Range[0,20]+1)/5 (* or *) LinearRecurrence[{12,-11},{2,20},20] (* _Harvey P. Dale_, Mar 13 2024 *)

%o (Magma) [(9*11^n+1)/5: n in [0..30]];

%K nonn,easy

%O 0,1

%A _Vincenzo Librandi_, Nov 10 2011