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 A387440 #12 Aug 31 2025 06:34:23 %S A387440 9,5,9,4,9,2,9,7,3,6,1,4,4,9,7,3,8,9,8,9,0,3,6,8,0,5,7,0,6,6,3,2,7,6, %T A387440 9,9,0,6,2,4,5,4,8,4,8,4,2,2,1,6,1,9,5,5,0,4,4,4,9,5,0,5,8,9,9,5,1,9, %U A387440 0,3,0,8,2,9,6,2,8,6,6,6,6,9,7,0,5,0,4,2,8,0,6,7,3,6,0,7,2,3,5,9,2,9,3,5,4,0,8,5,0,5,7,4,4,8,6,9,8,9 %N A387440 Decimal expansion of cos(Pi/11). %H A387440 R. J. Mathar, <a href="https://vixra.org/abs/2210.0026">Reduction formulas of the cosine of integer fractions of pi</a>, (2008) vixra:2210.0026 %H A387440 <a href="/index/Al#algebraic_05">Index entries for algebraic numbers, degree 5</a> %F A387440 Largest of the 5 real-valued roots of 32*x^5 -16*x^4 -32*x^3 +12*x^2 +6*x-1 =0. %F A387440 Equals sin(9*Pi/22). %e A387440 0.95949297361449738989... %Y A387440 Cf. A019678. %K A387440 nonn,cons,new %O A387440 0,1 %A A387440 _R. J. Mathar_, Aug 29 2025