%I #18 Sep 08 2022 08:44:54
%S 1,2,5,162,329,820,26569,53958,134485,4357478,8849441,22056360,
%T 714652961,1451362282,3617377525,117207443082,238032263689,
%U 593271970460,19222735318409,39038742607278,97300220532965,3152645799662158,6402591819857281,15957829439376720
%N Denominators of continued fraction convergents to sqrt(269).
%H Vincenzo Librandi, <a href="/A041505/b041505.txt">Table of n, a(n) for n = 0..200</a>
%H <a href="/index/Rec">Index entries for linear recurrences with constant coefficients</a>, signature (0,0,164,0,0,1).
%F G.f.: -(x^4-2*x^3+5*x^2+2*x+1) / (x^6+164*x^3-1). - _Colin Barker_, Nov 18 2013
%F a(n) = 164*a(n-3) + a(n-6) for n>5. - _Vincenzo Librandi_, Dec 19 2013
%t Denominator[Convergents[Sqrt[269], 30]] (* _Vincenzo Librandi_, Dec 19 2013 *)
%t LinearRecurrence[{0,0,164,0,0,1},{1,2,5,162,329,820},30] (* _Harvey P. Dale_, Jan 22 2019 *)
%o (Magma) I:=[1,2,5,162,329,820]; [n le 6 select I[n] else 164*Self(n-3)+Self(n-6): n in [1..30]]; // _Vincenzo Librandi_, Dec 19 2013
%Y Cf. A041504, A040252.
%K nonn,frac,easy
%O 0,2
%A _N. J. A. Sloane_.
%E More terms from _Colin Barker_, Nov 18 2013