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 A153318 #27 Aug 21 2025 06:45:10
%S A153318 1,11,23,241,505,5291,11087,116161,243409,2550251,5343911,55989361,
%T A153318 117322633,1229215691,2575754015,26986755841,56549265697,592479412811,
%U A153318 1241508091319,13007560326001,27256628743321,285573847759211,598404324261743,6269617090376641,13137638505015025
%N A153318 Numerators of continued fraction convergents to sqrt(6/5).
%H A153318 Paolo Xausa, <a href="/A153318/b153318.txt">Table of n, a(n) for n = 0..1000</a>
%H A153318 <a href="/index/Rec#order_04">Index entries for linear recurrences with constant coefficients</a>, signature (0,22,0,-1).
%F A153318 For n>0, a(2*n) = 2*a(2*n-1) + a(2*n-2) and a(2*n+1) = 10*a(2*n) + a(2*n-1).
%F A153318 G.f.: (1+11*x+x^2-x^3)/(1-22*x^2+x^4). - _Colin Barker_, Jan 01 2012
%e A153318 The initial convergents are 1, 11/10, 23/21, 241/220, 505/461, 5291/4830, 11087/10121, 116161/106040, 243409/222201, 2550251/2328050, 55989361/4878301, ...
%t A153318 Numerator[Convergents[Sqrt[6/5],20]] (* or *) LinearRecurrence[{0,22,0,-1},{1,11,23,241},20] (* _Harvey P. Dale_, Jul 30 2018 *)
%Y A153318 Cf. A000129, A001333, A142238, A142239, A153315, A153316, A153317.
%K A153318 nonn,changed
%O A153318 0,2
%A A153318 _Charlie Marion_, Jan 07 2009