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 A041032 #24 Jul 09 2025 00:10:45
%S A041032 4,5,9,23,32,55,472,527,999,2525,3524,6049,51916,57965,109881,277727,
%T A041032 387608,665335,5710288,6375623,12085911,30547445,42633356,73180801,
%U A041032 628079764,701260565,1329340329,3359941223
%N A041032 Numerators of continued fraction convergents to sqrt(21).
%H A041032 Vincenzo Librandi, <a href="/A041032/b041032.txt">Table of n, a(n) for n = 0..200</a>
%H A041032 <a href="/index/Rec">Index entries for linear recurrences with constant coefficients</a>, signature (0,0,0,0,0,110,0,0,0,0,0,-1).
%F A041032 a(n) = 110*a(n-6)-a(n-12). G.f.: -(x^11 -4*x^10 +5*x^9 -9*x^8 +23*x^7 -32*x^6 -55*x^5 -32*x^4 -23*x^3 -9*x^2 -5*x -4)/((x^4 -5*x^2 +1) *(x^8 +5*x^6 +24*x^4 +5*x^2 +1)). - _Colin Barker_, Jul 16 2012
%t A041032 Table[Numerator[FromContinuedFraction[ContinuedFraction[Sqrt[21],n]]],{n,1,50}] (* _Vladimir Joseph Stephan Orlovsky_, Mar 17 2011 *)
%t A041032 Numerator[Convergents[Sqrt[21],50]] (* _Harvey P. Dale_, Apr 20 2012 *)
%Y A041032 Cf. A010477, A041033.
%K A041032 nonn,cofr,frac,easy
%O A041032 0,1
%A A041032 _N. J. A. Sloane_