login
This site is supported by donations to The OEIS Foundation.

 

Logo

Please make a donation to keep the OEIS running. We are now in our 55th year. In the past year we added 12000 new sequences and reached 8000 citations (which often say "discovered thanks to the OEIS"). We need to raise money to hire someone to manage submissions, which would reduce the load on our editors and speed up editing.
Other ways to donate

Hints
(Greetings from The On-Line Encyclopedia of Integer Sequences!)
A199176 Decimal expansion of x<0 satisfying x^2+2*x*cos(x)=1. 3
1, 3, 0, 1, 2, 0, 1, 7, 3, 3, 1, 4, 1, 9, 1, 1, 4, 0, 0, 7, 9, 8, 3, 9, 7, 3, 6, 4, 4, 4, 0, 2, 6, 4, 5, 2, 2, 1, 9, 1, 3, 0, 0, 6, 5, 7, 4, 3, 0, 3, 0, 4, 8, 9, 2, 6, 9, 4, 6, 0, 5, 7, 9, 4, 6, 6, 0, 3, 7, 1, 9, 0, 5, 4, 5, 5, 9, 6, 8, 1, 3, 3, 2, 4, 3, 2, 9, 6, 9, 4, 8, 2, 3, 0, 7, 2, 9, 2, 9 (list; constant; graph; refs; listen; history; text; internal format)
OFFSET

1,2

COMMENTS

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

LINKS

Table of n, a(n) for n=1..99.

EXAMPLE

negative: -1.301201733141911400798397364440264522...

positive:  0.444416809391791633213083601823107078...

MATHEMATICA

a = 1; b = 2; 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]  (* A199176 *)

r = x /. FindRoot[f[x] == g[x], {x, .44, .45}, WorkingPrecision -> 110]

RealDigits[r]  (* A199177 *)

CROSSREFS

Cf. A199170.

Sequence in context: A274876 A065718 A025428 * A021336 A100749 A124027

Adjacent sequences:  A199173 A199174 A199175 * A199177 A199178 A199179

KEYWORD

nonn,cons

AUTHOR

Clark Kimberling, Nov 04 2011

STATUS

approved

Lookup | Welcome | Wiki | Register | Music | Plot 2 | Demos | Index | Browse | More | WebCam
Contribute new seq. or comment | Format | Style Sheet | Transforms | Superseeker | Recent
The OEIS Community | Maintained by The OEIS Foundation Inc.

License Agreements, Terms of Use, Privacy Policy. .

Last modified December 15 00:30 EST 2019. Contains 329988 sequences. (Running on oeis4.)