A200354 Decimal expansion of least x > 0 satisfying x^2 + 4*x + 1 = tan(x).

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

Offset

1,2

Comments

See A200338 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

1.45977234643857003377170287358954477353...

Mathematica

a = 1; b = 4; c = 1;
f[x_] := a*x^2 + b*x + c; g[x_] := Tan[x]
Plot[{f[x], g[x]}, {x, -.1, Pi/2}, {AxesOrigin -> {0, 0}}]
r = x /. FindRoot[f[x] == g[x], {x, 1.4, 1.5}, WorkingPrecision -> 110]
RealDigits[r]   (* A200354 *)

Prog

(PARI) solve(x=1, 3/2, x^2 + 4*x + 1 - tan(x)) \\ Michel Marcus, Aug 05 2018

Crossrefs

Cf. A200338.

Sequence in context: A356509 A371936 A069228 * A328485 A021689 A178610

Adjacent sequences: A200351 A200352 A200353 * A200355 A200356 A200357

Keyword

nonn,cons

Author

Clark Kimberling, Nov 17 2011

Status

approved