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 A104954 #19 Feb 16 2025 08:32:57 %S A104954 1,2,9,9,0,3,8,1,0,5,6,7,6,6,5,7,9,7,0,1,4,5,5,8,4,7,5,6,1,2,9,4,0,4, %T A104954 2,7,5,2,0,7,1,0,3,9,4,0,3,5,7,7,8,5,4,7,1,0,4,1,8,5,5,2,3,4,5,8,8,9, %U A104954 4,9,7,6,2,6,8,1,6,0,0,0,2,7,8,1,0,8,5,9,6,4,0,0,6,7,9,3,6,4,3,1,7,5,6,7,1 %N A104954 Decimal expansion of the area of the regular triangle with circumradius 1. %C A104954 Equivalently, the area in the complex plane of the smallest convex set containing all order-3 roots of unity. %H A104954 Eric Weisstein et al., <a href="https://mathworld.wolfram.com/RootofUnity.html">Root of Unity</a>. %H A104954 Eric Weisstein's World of Mathematics, <a href="https://mathworld.wolfram.com/deMoivreNumber.html">de Moivre Number</a>. %H A104954 I. J. Zucker and G. S. Joyce, <a href="https://doi.org/10.1017/S0305004101005254">Special values of the hypergeometric series II</a>, Math. Proc. Camb. Phil. Soc. 131 (2001) 309-319. %H A104954 <a href="/index/Al#algebraic_02">Index entries for algebraic numbers, degree 2</a> %F A104954 Equals 3*sqrt(3)/4. %F A104954 Equals (1/2)*A104956. %F A104954 Equals 2F1(1/6,1/3 ; 1/2 ; 25/27). [Zucker] - _R. J. Mathar_, Jun 24 2024 %e A104954 1.299038105676657970145584756129404275207103940357785471... %t A104954 RealDigits[N[Floor[n/2]*Sin[(2*Pi)/n] - Sin[(4*Pi*Floor[n/2])/n]/2 /. n -> 3, 108]][[1]] %Y A104954 Cf. A104955, A104956, A104957. %K A104954 nonn,cons %O A104954 1,2 %A A104954 Joseph Biberstine (jrbibers(AT)indiana.edu), Mar 30 2005 %E A104954 Edited by _Georg Fischer_, Jul 29 2021