A198122 Decimal expansion of least x having 2*x^2-4x=-cos(x).

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

Offset

0,1

Comments

See A197737 for a guide to related sequences. The Mathematica program includes a graph.

Links

Table of n, a(n) for n=0..100.

Index entries for transcendental numbers.

Example

least x: 0.27932077973816506128059339665539554...
greatest x: 2.123633334519982394198770246411061...

Mathematica

a = 2; b = -4; c = -1;
f[x_] := a*x^2 + b*x; g[x_] := c*Cos[x]
Plot[{f[x], g[x]}, {x, -1, 3}]
r1 = x /. FindRoot[f[x] == g[x], {x, .27, .28}, WorkingPrecision -> 110]
RealDigits[r1](* A198122 *)
r2 = x /. FindRoot[f[x] == g[x], {x, 2.1, 2.2}, WorkingPrecision -> 110]
RealDigits[r2](* A198123 *)

Prog

(PARI) solve(x=0, 1, 2*x^2-4*x+cos(x)) \\ Charles R Greathouse IV, Apr 10 2026

Crossrefs

Cf. A197737.

Sequence in context: A395259 A240961 A303128 * A021362 A371803 A381701

Adjacent sequences: A198119 A198120 A198121 * A198123 A198124 A198125

Keyword

nonn,cons

Author

Clark Kimberling, Oct 21 2011

Status

approved