A199082 Decimal expansion of x < 0 satisfying x^2 + 2*sin(x) = 2.

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

Offset

1,2

Comments

See A198866 for a guide to related sequences. The Mathematica program includes a graph.

Links

G. C. Greubel, Table of n, a(n) for n = 1..10000

Example

negative: -1.96188424641083489341928077977489...
positive:  0.77498081442304344595859350247040...

Mathematica

a = 1; b = 2; c = 2;
f[x_] := a*x^2 + b*Sin[x]; g[x_] := c
Plot[{f[x], g[x]}, {x, -2, 2}, {AxesOrigin -> {0, 0}}]
r = x /. FindRoot[f[x] == g[x], {x, -1.97, -1.96}, WorkingPrecision -> 110]
RealDigits[r](* A199082 *)
r = x /. FindRoot[f[x] == g[x], {x, .77, .78}, WorkingPrecision -> 110]
RealDigits[r](* A199083 *)

Prog

(PARI) a=1; b=2; c=2; solve(x=-2, 0, a*x^2 + b*sin(x) - c) \\ G. C. Greubel, Feb 20 2019
(Sage) a=1; b=2; c=2; (a*x^2 + b*sin(x)==c).find_root(-2, 0, x) # G. C. Greubel, Feb 20 2019

Crossrefs

Cf. A198866, A199083.

Sequence in context: A021108 A021840 A198582 * A358644 A220669 A064230

Adjacent sequences: A199079 A199080 A199081 * A199083 A199084 A199085

Keyword

nonn,cons

Author

Clark Kimberling, Nov 02 2011

Status

approved