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 A071884 #7 Nov 04 2013 12:21:57 %S A071884 37,77,170,714,3450,10414,68145,303610,721305,1815066,17782782, %T A071884 4598150,68178460,133118649,585506070,20663527908,777507763200, %U A071884 264506067126,73112062114130,5907184479605316,516068243814152148 %N A071884 Trajectory of 37 under map x -> A002487(x)*A002487(x+1). %C A071884 All smaller starting values lead into a cycle after a small number of steps; this appears to have an infinite trajectory. %p A071884 # n is starting value, m is length of trajectory to compute %p A071884 f := proc(n,m) local t1,i,j; t1 := [n]; for i from 2 to m do j := t1[i-1]; t1 := [op(t1), A002487(j)*A002487(j+1)]; od: t1; end; %Y A071884 Cf. A002487, A071885, A071886, A071887. %K A071884 nonn %O A071884 0,1 %A A071884 _N. J. A. Sloane_ and _J. H. Conway_, Jun 10 2002