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.

A199183 Decimal expansion of greatest x satisfying x^2 + 3*x*cos(x) = 1.

Original entry on oeis.org

3, 2, 7, 7, 4, 6, 4, 6, 6, 3, 4, 1, 3, 7, 3, 0, 5, 8, 7, 3, 4, 5, 8, 7, 7, 2, 7, 7, 9, 1, 0, 8, 3, 5, 7, 1, 7, 7, 4, 7, 8, 5, 8, 8, 5, 4, 4, 7, 9, 5, 3, 1, 4, 9, 0, 1, 3, 4, 2, 1, 2, 3, 2, 8, 6, 6, 2, 2, 6, 8, 2, 3, 3, 2, 8, 8, 5, 6, 8, 8, 0, 4, 7, 6, 8, 9, 7, 7, 7, 9, 5, 6, 8, 9, 7, 5, 7, 0, 0
Offset: 1

Views

Author

Clark Kimberling, Nov 04 2011

Keywords

Comments

See A199170 for a guide to related sequences. The Mathematica program includes a graph.

Examples

			least: -1.3606727725137972152286027487379925...
greatest: 3.27746466341373058734587727791083...
		

Crossrefs

Programs

  • Mathematica
    a = 1; b = 3; c = 1;
    f[x_] := a*x^2 + b*x*Cos[x]; g[x_] := c
    Plot[{f[x], g[x]}, {x, -2 Pi, 2 Pi}, {AxesOrigin -> {0, 0}}]
    r = x /. FindRoot[f[x] == g[x], {x, -1.4, -1.3}, WorkingPrecision -> 110]
    RealDigits[r]   (* A199182  least of four roots *)
    r = x /. FindRoot[f[x] == g[x], {x, 3.27, 3.28}, WorkingPrecision -> 110]
    RealDigits[r]   (* A199183  greatest of four roots *)

Extensions

a(92) onwards corrected by Georg Fischer, Aug 03 2021