This is a front-end for the Online Encyclopedia of Integer Sequences, made by Christian Perfect. The idea is to provide OEIS entries in non-ancient HTML, and then to think about how they're presented visually. The source code is on GitHub.
%I A041691 #21 Jul 09 2025 01:15:52
%S A041691 1,9,10,19,181,6897,62254,69151,131405,1251796,47699653,430548673,
%T A041691 478248326,908796999,8657421317,329890807045,2977674684722,
%U A041691 3307565491767,6285240176489,59874727080168,2281524869222873,20593598550086025,22875123419308898
%N A041691 Denominators of continued fraction convergents to sqrt(365).
%H A041691 Vincenzo Librandi, <a href="/A041691/b041691.txt">Table of n, a(n) for n = 0..200</a>
%H A041691 <a href="/index/Rec#order_10">Index entries for linear recurrences with constant coefficients</a>, signature (0, 0, 0, 0, 6916, 0, 0, 0, 0, 1).
%F A041691 G.f.: -(x^8 -9*x^7 +10*x^6 -19*x^5 +181*x^4 +19*x^3 +10*x^2 +9*x +1) / (x^10 +6916*x^5 -1). - _Colin Barker_, Nov 22 2013
%F A041691 a(n) = 6916*a(n-5) + a(n-10) for n>9. - _Vincenzo Librandi_, Dec 23 2013
%t A041691 Denominator[Convergents[Sqrt[365], 30]] (* _Vincenzo Librandi_, Dec 23 2013 *)
%t A041691 LinearRecurrence[{0,0,0,0,6916,0,0,0,0,1},{1,9,10,19,181,6897,62254,69151,131405,1251796},30] (* _Harvey P. Dale_, Jun 03 2019 *)
%o A041691 (Magma) I:=[1,9,10,19,181,6897,62254,69151,131405, 1251796]; [n le 10 select I[n] else 6916*Self(n-5)+Self(n-10): n in [1..40]]; // _Vincenzo Librandi_, Dec 23 2013
%Y A041691 Cf. A041690, A040345, A176980.
%K A041691 nonn,frac,easy
%O A041691 0,2
%A A041691 _N. J. A. Sloane_
%E A041691 More terms from _Colin Barker_, Nov 22 2013