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 A001957 M2302 N0908 #36 Dec 27 2021 10:46:34
%S A001957 0,1,3,4,5,6,8,9,10,12,13,14,16,17,18,19,21,22,23,25,26,27,29,30,31,
%T A001957 33,34,35,36,38,39,40,42,43,44,46,47,48,49,51,52,53,55,56,57,59,60,61,
%U A001957 62,64,65,66,68,69,70,72,73,74,75,77,78,79,81,82,83,85,86,87
%N A001957 u-pile positions in the 3-Wythoff game with i=1.
%C A001957 See Connell (1959) for further information.
%C A001957 The complement is A001960. - _Omar E. Pol_, Jan 06 2009
%D A001957 N. J. A. Sloane, A Handbook of Integer Sequences, Academic Press, 1973 (includes this sequence).
%D A001957 N. J. A. Sloane and Simon Plouffe, The Encyclopedia of Integer Sequences, Academic Press, 1995 (includes this sequence).
%H A001957 T. D. Noe, <a href="/A001957/b001957.txt">Table of n, a(n) for n = 0..10000</a>
%H A001957 Ian G. Connell, <a href="http://dx.doi.org/10.4153/CMB-1959-024-3">A generalization of Wythoff's game</a>, Canad. Math. Bull. 2 (1959) 181-190.
%F A001957 a(n) = floor((n+1/3)*(sqrt(13)-1)/2). - _R. J. Mathar_, Feb 14 2011
%t A001957 Table[Floor[(n + 1/3)*(Sqrt[13] - 1)/2], {n, 0, 100}] (* _T. D. Noe_, Aug 17 2012 *)
%Y A001957 Cf. A001954, A001958-A001960, A001963-A001968.
%K A001957 nonn,easy
%O A001957 0,3
%A A001957 _N. J. A. Sloane_
%E A001957 Edited by _N. J. A. Sloane_, Dec 27 2021