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 A387449 #7 Aug 31 2025 06:37:59 %S A387449 9,9,4,8,6,9,3,2,3,3,9,1,8,9,5,1,4,6,3,2,1,3,5,3,3,0,9,8,8,3,7,1,9,4, %T A387449 9,3,0,0,3,9,6,5,2,2,2,2,9,1,2,4,4,2,1,0,8,6,6,9,6,3,6,1,6,8,1,4,3,7, %U A387449 9,2,9,4,3,1,5,7,6,8,2,5,9,7,8,6,5,1,7,8,9,5,5,3,4,2,3,3,2,5,2,5,5,1,3,5,9,0,1,7,5,1,5,7,7,2,7,5,6,3 %N A387449 Decimal expansion of cos(Pi/31). %H A387449 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 A387449 <a href="/index/Al#algebraic_15">Index entries for algebraic numbers, degree 15</a> %F A387449 Equals sin(29*Pi/62). %F A387449 Largest of the 15 real-valued roots of 32768*x^15 -16384*x^14 -114688*x^13 +53248*x^12 +159744*x^11 -67584*x^10 -112640*x^9 +42240*x^8 +42240*x^7 -13440*x^6 -8064*x^5 +2016*x^4 +672*x^3 -112*x^2 -16*x +1 =0. %e A387449 0.99486932339189514632... %Y A387449 Cf. A132700. %K A387449 nonn,cons,new %O A387449 0,1 %A A387449 _R. J. Mathar_, Aug 29 2025