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 A042280 #14 Jul 09 2025 02:31:07 %S A042280 25,26,129,671,800,1471,9626,11097,54014,65111,444680,509791,954471, %T A042280 5282146,22083055,27365201,1390343105,1417708306,7061176329, %U A042280 36723589951,43784766280,80508356231,526834903666 %N A042280 Numerators of continued fraction convergents to sqrt(666). %H A042280 Vincenzo Librandi, <a href="/A042280/b042280.txt">Table of n, a(n) for n = 0..200</a> %H A042280 <a href="/index/Rec#order_32">Index entries for linear recurrences with constant coefficients</a>, signature (0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 54730402, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, -1). %t A042280 Numerator[Convergents[Sqrt[666], 30]] (* _Vincenzo Librandi_, Nov 20 2013 *) %Y A042280 Cf. A042281. %K A042280 nonn,cofr,frac,easy %O A042280 0,1 %A A042280 _N. J. A. Sloane_