cp's OEIS Frontend

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.

A229985 Decimal expansion of the lower limit of the convergents of the continued fraction [1, 1/3, 1/9, 1/27, ... ].

This page as a plain text file.
%I A229985 #8 Oct 10 2013 09:18:59
%S A229985 1,1,1,9,9,9,3,4,0,9,9,7,2,9,5,8,7,4,0,9,1,4,2,8,3,2,4,8,2,6,0,9,5,3,
%T A229985 2,2,9,9,6,3,8,0,1,7,0,2,8,1,5,5,2,5,0,7,0,5,8,8,5,1,0,7,5,4,8,6,6,5,
%U A229985 4,1,5,4,6,4,6,4,2,7,4,9,8,8,2,5,8,4
%N A229985 Decimal expansion of the lower limit of the convergents of the continued fraction [1, 1/3, 1/9, 1/27, ... ].
%C A229985 Since sum{3^(-k), k = 0,1,2,...} converges, the convergents of [1, 1/3, 1/9, 1/27, ... ] diverge, by the Seidel Convergence Theorem.  However, the odd-numbered convergents converge, as do the even-numbered convergents.  In the Example section, these limits are denoted by u and v.
%e A229985 u = 1.119... = [1, 8, 2, 1, 242, 8, 1, 6560, 26, 1, 177146, 80, 1,...];
%e A229985 v = 3.668... = [3, 1, 2, 80, 1, 8, 2186, 1, 26, 59048, 1, 80, ...].
%e A229985 In both cases, every term of the continued fraction has the form 3^m - 1.
%t A229985 $MaxExtraPrecision = Infinity; z = 500; t = Table[3^(-n), {n, 0, z}]; u = N[Convergents[t][[z - 1]], 120]; v = N[Convergents[t][[z]], 120];
%t A229985 RealDigits[u] (* A229985 *)
%t A229985 RealDigits[v] (* A229986 *)
%Y A229985 Cf. A229986, A024023.
%K A229985 nonn,cons
%O A229985 1,4
%A A229985 _Clark Kimberling_, Oct 06 2013