login

Year-end appeal: Please make a donation to the OEIS Foundation to support ongoing development and maintenance of the OEIS. We are now in our 61st year, we have over 378,000 sequences, and we’ve reached 11,000 citations (which often say “discovered thanks to the OEIS”).

A199614
Decimal expansion of greatest x satisfying x^2+4*x*cos(x)=sin(x).
3
3, 5, 5, 3, 2, 4, 1, 6, 8, 0, 6, 8, 2, 8, 9, 2, 5, 2, 3, 9, 5, 7, 2, 6, 5, 5, 5, 6, 2, 3, 4, 4, 9, 4, 9, 0, 2, 0, 6, 7, 7, 6, 2, 6, 1, 8, 6, 1, 7, 2, 3, 9, 1, 5, 4, 2, 8, 6, 0, 0, 4, 2, 8, 8, 8, 6, 6, 0, 4, 0, 7, 4, 9, 0, 2, 5, 6, 2, 7, 1, 6, 0, 1, 8, 7, 4, 7, 3, 5, 7, 2, 1, 8, 0, 8, 2, 6, 7, 7
OFFSET
1,1
COMMENTS
See A199597 for a guide to related sequences. The Mathematica program includes a graph.
EXAMPLE
least: -1.077309917524072030339979615126813664791...
greatest: 3.553241680682892523957265556234494902...
MATHEMATICA
a = 1; b = 4; c = 1;
f[x_] := a*x^2 + b*x*Cos[x]; g[x_] := c*Sin[x]
Plot[{f[x], g[x]}, {x, -2, 4}, {AxesOrigin -> {0, 0}}]
r = x /. FindRoot[f[x] == g[x], {x, -1.1, -1.0}, WorkingPrecision -> 110]
RealDigits[r] (* A199613, least of 4 roots *)
r = x /. FindRoot[f[x] == g[x], {x, 3.5, 3.6}, WorkingPrecision -> 110]
RealDigits[r] (* A199614, greatest of 4 roots *)
CROSSREFS
Cf. A199597.
Sequence in context: A320477 A110551 A141334 * A129488 A211023 A279494
KEYWORD
nonn,cons
AUTHOR
Clark Kimberling, Nov 08 2011
STATUS
approved