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 A064668 #5 Mar 30 2012 16:49:13 %S A064668 73,138,131,253,248,234,219,139,264,247,242,229,438,413,397,756,716, %T A064668 679,647,1242,1184,1130,1076,1027,993,630,594,564,537,337,639,608,576, %U A064668 547,1041,656,626,598,569,1080,1023,948,904,871,844,805,772,733 %N A064668 Regard A064413 as giving a permutation of the positive integers; sequence gives second infinite cycle, reading backwards beginning at its smallest term, 73. %H A064668 J. C. Lagarias, E. M. Rains and N. J. A. Sloane, <a href="http://arXiv.org/abs/math.NT/0204011">The EKG sequence</a>, Exper. Math. 11 (2002), 437-446. %H A064668 <a href="/index/Ed#EKG">Index entries for sequences related to EKG sequence</a> %e A064668 Permutation has cycles (1) (2) (3, 4, 6, 9, 10, 5) ( ..., 20, 18, 12, 7, 14, 13, 28, 26, ...) (8) ... %Y A064668 Cf. A064413, A064665-A064669. %K A064668 nonn %O A064668 1,1 %A A064668 _N. J. A. Sloane_, Oct 11 2001