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 A105790 #4 Mar 30 2012 17:31:15
%S A105790 1,4,4,6,8,9,11,13,14,16,17,19,21,23,25,26,27,30,31,33,34,36,38,40,41,
%T A105790 43,45,46,47,49,53,53,54,56,58,60,61,62,65,66,67,70,71,72,75,76,78,80,
%U A105790 83,83,84,87,89,89,91,93,94,96,98,99,100,103,105,107,107,109,112,112
%N A105790 Number of bisections to an inscribed triangle to approximate Pi (A000796) to n decimal digits of accuracy.
%D A105790 Howard Anton, Irl C. Bivens and Stephen L. Davis, Calculus, Early Transcendentals, 7th Edition, John Wiley & Sons, Inc., NY, Section 6.1 An Overview of the Area Problem, page 372-377.
%D A105790 William Dunham, The Calculus Gallery, Masterpieces from Newton to Lebesgue, Princeton University Press, Princeton, NJ 2005, page 56-57.
%F A105790 a(n) = 3*2^n*sqrt(2- sqrt(2+ sqrt(2+ ... sqrt(2+ sqrt(3))...))).
%F A105790 A(n) in Table 6.1.1 = Sin( 2Pi/n )*n/2. - Anton.
%t A105790 $MaxExtraPrecision =128; p=RealDigits[ Pi, 10, 100][[1]]; f[n_] := 3*2^(n)*Sqrt[2 - Nest[ Sqrt[2 + # ] &, Sqrt[3], n - 1]]; g[n_] := Block[{k = 1, q = Take[p, n + 1]}, While[ Take[ RealDigits[ f[k], 10, 100][[1]], n + 1] != q, k++ ]; k]; Table[ g[n], {n, 69}]
%Y A105790 Cf. A000796.
%K A105790 nonn,base
%O A105790 1,2
%A A105790 _Robert G. Wilson v_, Apr 20 2005